Drying apparatus, coating machine, and drying method

Abstract

Disclosed herein are a drying apparatus, a coating machine, and a drying method. The drying apparatus comprises a fresh air main pipe, an exhaust main pipe, an NMP recovery system, and at least two drying ovens. Each drying oven is provided with a drying region, and electrode sheets are dried as they pass through each drying oven. Each drying oven is equipped with a pressure detection apparatus, which is used to detect an air pressure value inside the drying oven as a partial air pressure value. A fresh air inlet of each drying oven is connected to the fresh air main pipe by means of a pipeline, the fresh air main pipe is equipped with a main fresh air fan, and a fresh air valve is disposed at the fresh air inlet of each drying oven. An exhaust outlet of each drying oven is connected to the exhaust main pipe by means of a pipeline, the exhaust main pipe is equipped with a main exhaust fan, and an exhaust valve is disposed at the exhaust outlet of each drying oven. The NMP recovery system is used to recover N-methylpyrrolidone, the fresh air main pipe is connected to an outlet of the NMP recovery system, and the exhaust main pipe is connected to an inlet of the NMP recovery system.

Description

Drying equipment, coating machine and drying method

[0001] Cross-references to related applications

[0002] This disclosure is based on and claims priority to Chinese Patent Application No. 202411044533.X, filed on July 31, 2024, entitled "Drying Apparatus, Coating Machine and Drying Method", the entire contents of which are incorporated herein by reference. Technical Field

[0003] This disclosure relates to the field of battery manufacturing technology, and in particular to drying apparatus, coating machine and drying method. Background Technology

[0004] The application of new energy batteries in daily life and industry is becoming increasingly widespread. For example, new energy vehicles equipped with batteries are already widely used, and batteries are also increasingly being applied in energy storage. In new energy vehicles equipped with batteries, the batteries can provide all or part of the power. In the field of energy storage, batteries can be installed in energy storage boxes or directly on the user side.

[0005] The quality of the electrode plates in a battery is related to the battery's capacity, energy density, cycle life, and other performance characteristics. Therefore, improving the manufacturing quality of electrode plates is one of the topics that the industry needs to study. Summary of the Invention

[0006] To solve the above-mentioned technical problems, this disclosure provides a drying apparatus, a coating machine, and a drying method that can improve the quality of electrode sheets.

[0007] This disclosure is achieved through the following technical solution.

[0008] This disclosure provides a drying apparatus, comprising: at least two interconnected drying ovens, each oven having a drying area, wherein the electrode is dried as it passes through each oven; each oven is equipped with a pressure detection device for detecting the pressure value inside the oven as a partial pressure value; each oven has a fresh air inlet for incoming fresh air and an exhaust outlet for discharging gas from the oven; a main fresh air duct, wherein the fresh air inlets of each oven are respectively connected to the main fresh air duct via pipes; the main fresh air duct is equipped with a main fresh air fan; and each oven's fresh air inlet is equipped with a fresh air valve; and an exhaust duct, wherein the exhaust outlets of each oven are respectively connected to the exhaust duct via pipes; the exhaust duct is equipped with a main exhaust fan. Each oven is equipped with an exhaust valve at its exhaust vent. An NMP recovery system is used to recover N-methylpyrrolidone generated during the drying process of the electrodes in the drying area of ​​each oven. The fresh air main is connected to the outlet of the NMP recovery system, and the exhaust main is connected to the inlet of the NMP recovery system. Ovens whose partial air pressure value is not in the preset negative pressure value range are designated as ovens with pressure to be adjusted. When there is at least one oven with pressure to be adjusted, the output power of the main fresh air fan and the main exhaust fan, as well as the opening of the fresh air valve and the exhaust valve of the oven with pressure to be adjusted, are adjusted so that the partial air pressure value of the oven with pressure to be adjusted is in the preset negative pressure value range.

[0009] When the partial air pressure value of at least one oven is not within the preset negative pressure range, the partial air pressure values ​​of multiple ovens can be changed simultaneously by adjusting the output power of the main fresh air fan and the main exhaust fan, resulting in high adjustment efficiency. Moreover, by adjusting the opening degree of the fresh air valve and exhaust air valve of the oven to be adjusted, the amount of fresh air entering the oven and the amount of gas discharged after the drying operation can be changed. In this embodiment, the output power of the inverter of the main fresh air fan and the main exhaust fan is interlocked with the opening degree of the fresh air valve and the exhaust air valve. Through coordinated adjustment, the partial air pressure value of the oven to be adjusted is brought into the preset negative pressure range, thereby enabling the partial air pressure values ​​of each oven to quickly reach the condition of being within the preset negative pressure range. Therefore, this embodiment improves the uniformity of the drying effect, improves the quality of the electrode sheets, and has high adjustment efficiency.

[0010] In some embodiments, each oven is provided with a fresh air inlet for fresh air to enter and an exhaust vent for gas to exit the oven. Each oven exhaust vent is equipped with an NMP concentration measuring device for detecting the NMP concentration value passing through the exhaust vent. Each oven is equipped with a circulating fan for driving the circulating air returning from the drying area and the gas after the fresh air entering from the fresh air inlet converge toward the drying area. Ovens whose NMP concentration values ​​are not within the preset NMP concentration value range are designated as ovens with concentrations to be adjusted. When there is at least one oven with a concentration to be adjusted, the output power of the circulating fan and the opening of the fresh air valve and exhaust air valve of the oven with the concentration to be adjusted are adjusted so that the NMP concentration value of the oven with the concentration to be adjusted is within the preset NMP concentration value range.

[0011] When the NMP concentration value of at least one oven is not within the preset NMP concentration range, the NMP concentration value can be changed by adjusting the output power of the circulating fan. The NMP concentration value can also be changed by adjusting the opening degree of the fresh air valve and exhaust valve of the oven to be adjusted, thereby altering the amount of fresh air entering the oven and the amount of gas discharged after drying. This embodiment of the present disclosure interlocks the output power of the circulating fan with the opening degree of the fresh air valve and exhaust valve, and through coordinated adjustment, ensures that the NMP concentration value of the oven to be adjusted is within the preset NMP concentration range. This allows the NMP concentration values ​​of all ovens to quickly reach the condition of being within the preset NMP concentration range. Therefore, this embodiment of the present disclosure improves the uniformity of the drying effect, enhances the quality of the electrode sheets, and has high adjustment efficiency.

[0012] In some embodiments, each oven is equipped with a wind box inlet speed measuring device. The wind box inlet speed measuring device is used to detect the wind speed value of the gas after the circulating air and fresh air converge. If the wind speed value measured by the wind box inlet speed measuring device is not within the preset wind speed value range, the circulating fan is adjusted so that the wind speed value measured by the wind box inlet speed measuring device is within the preset wind speed value range.

[0013] The air inlet velocity measuring device is used to detect the wind speed value of the gas after the circulating air and fresh air converge. After the circulating air and fresh air converge, they are immediately blown towards the drying area. Therefore, by ensuring that the wind speed value measured by the air inlet velocity measuring device is within the preset wind speed range, the wind speed of the gas sent to the drying area is appropriate, thereby improving the uniformity of the wind speed blowing towards the electrode sheet and thus improving the quality of the electrode sheet.

[0014] In some embodiments, each oven is equipped with a fresh air fan and a fresh air speed measuring device at its fresh air inlet. The fresh air fan can adjust the air speed at the fresh air inlet, and the fresh air speed measuring device detects the air speed at the fresh air inlet. Each oven is equipped with an exhaust fan and an exhaust speed measuring device at its exhaust outlet. The exhaust fan can adjust the air speed at the exhaust outlet, and the exhaust speed measuring device detects the air speed at the exhaust outlet. When there is at least one oven with pressure to be adjusted, the output power of the main fresh air fan and the main exhaust fan, the opening degree of the fresh air valve and the exhaust air valve of the oven with pressure to be adjusted, and the output power of the fresh air fan and the exhaust fan are adjusted so that the partial pressure value of the oven with pressure to be adjusted is within a preset partial negative pressure value range. When there is at least one oven with concentration to be adjusted, the output power of the circulating fan of the oven with concentration to be adjusted, the opening degree of the fresh air valve and the exhaust air valve, and the output power of the fresh air fan and the exhaust fan are adjusted so that the partial NMP concentration value of the oven with concentration to be adjusted is within a preset partial NMP concentration value range.

[0015] In this way, the gas pressure value of each oven is within the preset negative pressure value range, and the NMP concentration value of each oven is within the preset NMP concentration value range, thereby improving the uniformity of the drying effect, improving the quality of the electrode sheets, and the adjustment efficiency is high.

[0016] In some embodiments, each oven is provided with a heat exchange device for heating the temperature of the gas after the confluence of circulating air and fresh air. In the case of at least one oven with a concentration to be adjusted, the heating temperature of the heat exchange device of the oven with the concentration to be adjusted is adjusted so that the NMP concentration value of the oven with the concentration to be adjusted is within a preset NMP concentration value range.

[0017] The heat exchanger is used to heat the gas after the circulating air and fresh air converge, thereby increasing the temperature of the gas blown into the drying area and thus drying the electrode. The higher the drying temperature of the electrode, the faster the NMP is generated, resulting in a higher NMP concentration value. Therefore, by changing the heating temperature of the heat exchanger, the NMP concentration value can be affected, allowing the NMP concentration value to be kept within a preset NMP concentration range.

[0018] In some embodiments, when there is at least one oven with an adjustable concentration, the output power of the main fresh air fan and / or the main exhaust fan is adjusted so that the NMP concentration value of the oven with the adjustable concentration is within a preset NMP concentration value range.

[0019] Thus, by adjusting the circulating fan, fresh air valve, exhaust air valve, fresh air fan, exhaust fan, and heat exchange device, and by also adjusting the output power of the main fresh air fan and / or the main exhaust fan, the rate of NMP concentration adjustment can be accelerated.

[0020] In some embodiments, the exhaust manifold is equipped with a total exhaust NMP concentration measuring device, which is used to detect the total NMP concentration value of the gas passing through the exhaust manifold. When there is at least one oven with an adjustable concentration and the total NMP concentration value is not within the preset total NMP concentration value range, the output power of the circulating fan of the oven with the adjustable concentration and the heating temperature of the heat exchange device are first adjusted to make the total NMP concentration value within the preset total NMP concentration value range. Then, the output power of the fresh air fan and the exhaust fan of the oven with the adjustable concentration, the opening degree of the fresh air valve and the exhaust air valve, and the heating temperature of the heat exchange device are adjusted to make the NMP concentration value of the oven with the adjustable concentration within the preset NMP concentration value range.

[0021] In this way, the total NMP concentration is first brought into the preset range, allowing for the simultaneous adjustment of multiple ovens with different concentrations to be adjusted, which improves adjustment efficiency. Then, the individual NMP concentrations of the ovens to be adjusted are brought into the preset range, ensuring that the individual NMP concentrations of each oven are within the preset range. This process of coarse adjustment followed by fine adjustment not only improves adjustment efficiency but also enhances adjustment accuracy, thereby further improving the quality of the electrode sheets.

[0022] In some embodiments, the exhaust main duct is equipped with a total pressure detection device, which is used to detect the total air pressure value in the exhaust main duct. When there is at least one oven with an air pressure to be adjusted and the total air pressure value is not within the preset total negative pressure value range, the output power of the main fresh air fan and the main exhaust fan is first adjusted to make the total air pressure value within the preset total negative pressure value range. Then, the output power of the fresh air fan and the exhaust fan of the oven with the air pressure to be adjusted, as well as the opening degree of the fresh air valve and the exhaust air valve, are adjusted to make the partial air pressure value within the preset partial negative pressure value range.

[0023] In this way, by first ensuring that the total air pressure value is within the preset total negative pressure range, the individual air pressure values ​​of multiple ovens to be adjusted can be simultaneously affected, which is beneficial to improving the adjustment efficiency. Then, by ensuring that the individual air pressure values ​​of the ovens to be adjusted are within the preset individual air pressure range, the individual air pressure values ​​of each oven are within the preset individual negative pressure range. This process of coarse adjustment followed by fine adjustment not only improves the adjustment efficiency but also the adjustment accuracy, thereby further improving the quality of the electrode sheets.

[0024] In some embodiments, the main fresh air duct is equipped with a main fresh air velocity measuring device, which detects the air velocity in the main fresh air duct during the adjustment of the main fresh air fan; the main exhaust duct is equipped with a main exhaust velocity measuring device, which detects the air velocity in the main exhaust duct during the adjustment of the main exhaust fan.

[0025] This improves the accuracy of airflow regulation in the main fresh air duct and the main exhaust air duct, which in turn improves the accuracy of air pressure regulation and NMP concentration regulation, thereby improving the uniformity of drying effect, improving the quality of electrode sheets, and also increasing the efficiency of regulation.

[0026] In some embodiments, each oven includes a box body and a first air box and a second air box disposed within the box body. The first air box and the second air box are disposed opposite to each other and define a drying area between them. The first air box is provided with a first air inlet for gas to enter, and the second air box is provided with a second air inlet for gas to enter. The first air box has a first box wall facing the second air box, and the first box wall is provided with a plurality of first air nozzles with outlets facing the drying area. The first air nozzles are used to discharge the gas in the first air box toward the electrode. The box wall of the second air box facing the first air box is provided with a plurality of second air nozzles with outlets facing the drying area. The second air nozzles are used to discharge the gas in the second air box toward the electrode. The box body is provided with a fresh air inlet and an exhaust outlet. The fresh air inlet is connected to the first air inlet of the first air box and the second air inlet of the second air box, and the exhaust outlet is connected to the drying area.

[0027] In some embodiments, the chamber is provided with a return air duct, and a circulating fan is provided in the return air duct. The fresh air inlet and the exhaust outlet are respectively connected to the return air duct. The circulating fan is used to drive the gas in the drying area through the return air duct and through the exhaust outlet, so that some of the gas is discharged through the exhaust outlet. It also drives the remaining gas in the return air duct and the fresh air supplied from the fresh air inlet through the return air duct into the first air inlet and the second air inlet. A heat exchange device and an air box inlet speed measuring device are provided in the passage between the fresh air inlet and the first air inlet and the second air inlet of the return air duct.

[0028] In this way, some of the gas in the drying area can re-enter the first and second air boxes through the return air channel, and then be blown onto the electrode. The gas is recycled, and the recycled gas still has high heat, which helps to reduce heat loss and thus improve the heat utilization rate.

[0029] In some embodiments, a first air inlet valve is provided at the first air inlet of the first air box, and a second air inlet valve is provided at the second air inlet of the second air box. During the process of adjusting the output power of the circulating fan, the opening degree of the first air inlet valve and / or the second air inlet valve is adjusted.

[0030] In some embodiments, the first chamber wall is provided with a return air nozzle for the return air duct to allow gas in the drying area to flow back into the drying area.

[0031] The gas in the drying area can enter the return air channel through the return air nozzles set on the first chamber wall. This shortens the gas flow path, reduces the resistance along the circulation process and the fluctuation of wind speed, improves the uniformity of the lateral air volume, and enables the "surface" of the electrode coating to dry evenly. This achieves uniform drying of the inner and outer layers of the thick coating, improves lateral cracking and excessive drying at the edges, and thus improves the quality of the electrode sheet.

[0032] In some embodiments, a visual inspection device is provided on the outer side of the first box wall of the first air box, the visual inspection device being used to inspect the appearance of the electrode sheets located in the drying area.

[0033] The visual inspection device can adopt an AI visual inspection device, which can monitor the appearance of the electrode sheets inside the drying area online. When abnormalities occur in the appearance of the electrode sheets, the drying data can be corrected in a timely manner by controlling and adjusting the wind speed, negative pressure or NMP concentration, thereby improving the coating drying quality and efficiency.

[0034] In some embodiments, the visual inspection device is connected to the outside of the first housing wall via a mounting assembly configured to adjust the position of the visual inspection device along the width direction of the electrode.

[0035] This allows for a wider inspection of the electrode's appearance, further improving the quality and efficiency of coating and drying.

[0036] A second aspect of this disclosure provides a coating machine, comprising:

[0037] The first coating head is used to coat the first surface of the substrate to form an electrode sheet;

[0038] The first drying device and the second drying device formed by the above-mentioned drying device, wherein the first drying device is located downstream of the first coating head and is used to dry the first surface-facing electrode sheet;

[0039] The second coating head is located downstream of the first drying device and is used to coat the second surface of the electrode sheet.

[0040] The climbing mechanism is located downstream of the second coating head and upstream of the second drying device. The climbing mechanism is used to support the electrode from one side of the first surface of the electrode and pull the electrode so that the electrode enters the second drying device with the second surface facing upward. The second drying device is used to dry the electrode with the second surface facing upward.

[0041] A third aspect of this disclosure provides a drying method using a drying apparatus, which includes a fresh air main duct, an exhaust air main duct, and at least two connected drying ovens. Each oven has a drying zone. The electrode is dried as it passes through each oven. Each oven is equipped with a pressure detection device to detect the air pressure value inside the oven as a partial pressure value. Each oven has a fresh air inlet for fresh air intake and an exhaust outlet for exhausting gas from the oven. The fresh air inlets of each oven are connected to the fresh air main duct via pipes. The fresh air main duct is equipped with a main fresh air fan, and each oven's fresh air inlet is equipped with a fresh air valve. The exhaust outlets of each oven are connected to the exhaust air main duct via pipes. The exhaust air main duct is equipped with a main exhaust fan, and each oven's exhaust outlet is equipped with an exhaust valve. An NMP recovery system is used to recover N-methylpyrrolidone generated during the drying process of the electrode in the drying zone of each oven. The fresh air main duct is connected to the outlet of the NMP recovery system, and the exhaust air main duct is connected to the inlet of the NMP recovery system.

[0042] Drying methods include:

[0043] In the air pressure adjustment step, the oven whose partial air pressure value measured by the air pressure detection device is not in the preset partial negative pressure value range is regarded as the air pressure oven to be adjusted. When there is at least one air pressure oven to be adjusted, the output power of the main fresh air fan and the main exhaust fan and the opening degree of the fresh air valve and exhaust air valve of the air pressure oven to be adjusted are adjusted so that the partial air pressure value of the air pressure oven to be adjusted is in the preset partial negative pressure value range.

[0044] In some embodiments, each oven is equipped with a circulating fan, which drives the gas after the circulating air returning from the drying area and the fresh air entering from the fresh air inlet to flow toward the drying area; each oven is equipped with an air box inlet speed measuring device, which is used to detect the wind speed value of the gas after the circulating air and the fresh air converge.

[0045] The drying method, following the air pressure regulation step, also includes:

[0046] The wind speed adjustment procedure involves adjusting the circulating fan so that the wind speed measured by the air inlet speed measuring device is within the preset wind speed range when the wind speed value is not within the preset wind speed range.

[0047] In some embodiments, each oven is equipped with an NMP concentration measuring device at its exhaust vent. The NMP concentration measuring device is used to detect the NMP concentration value passing through the exhaust vent.

[0048] The drying method, after the air speed adjustment step, also includes:

[0049] In the concentration adjustment step, ovens whose NMP concentration values ​​measured by the NMP concentration measuring device are not within the preset NMP concentration value range are designated as ovens to be adjusted. If there is at least one oven to be adjusted, the output power of the circulating fan and the opening of the fresh air valve and exhaust air valve of the oven to be adjusted are adjusted so that the NMP concentration value of the oven to be adjusted is within the preset NMP concentration value range.

[0050] In some embodiments, each oven is equipped with a fresh air fan at its fresh air inlet, which is used to adjust the airflow speed at the fresh air inlet; and each oven is equipped with an exhaust fan at its exhaust outlet, which is used to adjust the airflow speed at the exhaust outlet.

[0051] In the air pressure regulation step, the output power of the fresh air fan and exhaust fan of the oven whose air pressure is to be regulated is also adjusted.

[0052] In the concentration adjustment step, the output power of the fresh air fan and exhaust fan of the oven to be adjusted is also adjusted.

[0053] In some embodiments, each oven is provided with a heat exchange device, which is used to heat the temperature of the gas after the circulating air and fresh air converge.

[0054] In the concentration adjustment step, the heating temperature of the heat exchange device of the oven to be adjusted is also adjusted.

[0055] In some embodiments, during the concentration adjustment step, the output power of the main fresh air fan and / or the main exhaust fan is also adjusted.

[0056] In some embodiments, the exhaust manifold is equipped with a total exhaust NMP concentration measuring device, which is used to detect the total NMP concentration value of the gas passing through the exhaust manifold.

[0057] The concentration adjustment steps include:

[0058] In the total concentration adjustment step, when there is at least one oven with a concentration to be adjusted and the total NMP concentration value is not within the preset total NMP concentration value range, the output power of the circulating fan of the oven with the concentration to be adjusted and the heating temperature of the heat exchange device are adjusted so that the total NMP concentration value is within the preset total NMP concentration value range.

[0059] In the concentration adjustment step, the output power of the fresh air fan and exhaust fan of the oven to be adjusted, the opening degree of the fresh air valve and exhaust air valve, and the heating temperature of the heat exchange device are adjusted so that the NMP concentration value of the oven to be adjusted is within the preset NMP concentration value range.

[0060] In some embodiments, the exhaust main is equipped with a total pressure detection device, which is used to detect the total air pressure value in the exhaust main.

[0061] The air pressure regulation steps include:

[0062] In the total air pressure adjustment step, when there is at least one oven with air pressure to be adjusted and the total air pressure value is not within the preset total negative pressure value range, the output power of the main fresh air fan and the main exhaust fan is adjusted so that the total air pressure value is within the preset total negative pressure value range.

[0063] The air pressure adjustment step involves adjusting the output power of the fresh air fan and exhaust fan of the oven to be adjusted, as well as the opening degree of the fresh air valve and exhaust air valve, so that the air pressure value is within the preset negative pressure value range.

[0064] In some embodiments, each oven is equipped with a visual inspection device in its drying zone, which is used to inspect the appearance of the electrode sheets after passing through the drying zone.

[0065] Drying methods also include:

[0066] The visual feedback step involves adjusting the air pressure, and / or the wind speed, and / or the concentration if the appearance measured by the visual inspection device does not meet the preset appearance reference standard.

[0067] In some embodiments, the drying method further includes:

[0068] Once the drying process for a batch of electrode sheets is completed, the final drying parameters are obtained. These parameters include the final output power of the main fresh air fan and the main exhaust fan, as well as the final opening degree of the fresh air valve and the exhaust air valve of the pressure-controlled oven to be adjusted. When the drying process for the next batch of electrode sheets begins, the drying device dries the next batch of electrode sheets according to the final drying parameters.

[0069] The beneficial effects of the embodiments disclosed herein include: providing a drying apparatus, coating machine, and drying method that can improve the quality of electrode sheets. Attached Figure Description

[0070] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the scope of this disclosure. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings:

[0071] Figure 1 is a schematic diagram of the composition of a drying system provided in some embodiments of this disclosure;

[0072] Figure 2 is a control system diagram of a drying system provided in some embodiments of this disclosure;

[0073] Figure 3 is a control system diagram of a drying system provided in some embodiments of this disclosure;

[0074] Figure 4 is a cross-sectional view of an oven provided in some embodiments of this disclosure;

[0075] Figure 5 is a simplified front view of an oven provided in some embodiments of this disclosure;

[0076] Figure 6 is a cross-sectional view along direction AA in Figure 5;

[0077] Figure 7 is a cross-sectional view along the BB direction in Figure 5;

[0078] Figure 8 is a simplified top view of an oven provided in some embodiments of this disclosure;

[0079] Figure 9 is a schematic diagram of the structure of a coating machine provided in some embodiments of this disclosure;

[0080] Figure 10 is a schematic flowchart of a first type of drying method provided in some embodiments of this disclosure;

[0081] Figure 11 is a schematic diagram of a second process of a drying method provided in some embodiments of this disclosure;

[0082] Figure 12 is a schematic diagram of a third process of a drying method provided in some embodiments of this disclosure;

[0083] Figure 13 is a schematic flowchart of the concentration adjustment steps provided in some embodiments of this disclosure;

[0084] Figure 14 is a schematic flowchart of the air pressure regulation steps provided in some embodiments of this disclosure;

[0085] Figure 15 is a schematic diagram of a fourth process of a drying method provided in some embodiments of this disclosure;

[0086] Figure 16 is a fifth process diagram of a drying method provided in some embodiments of this disclosure;

[0087] Figure 17 is a schematic flowchart of a drying method provided in some embodiments of this disclosure;

[0088] Figure 18 is a schematic flowchart of a drying parameter adjustment method provided in some embodiments of this disclosure;

[0089] Figure 19 is a schematic flowchart of a drying parameter adjustment method provided in some embodiments of this disclosure.

[0090] Figure 20 is a flowchart illustrating a first parameter adjustment method provided in some embodiments of this disclosure;

[0091] Figure 21 is a flowchart illustrating the first sub-parameter adjustment method provided in some embodiments of this disclosure;

[0092] Figure 22 is a flowchart illustrating the second sub-parameter adjustment method provided in some embodiments of this disclosure;

[0093] Figure 23 is a schematic flowchart of a first parameter adjustment method provided in some embodiments of this disclosure;

[0094] Figure 24 is a schematic flowchart of a first parameter adjustment method provided in some embodiments of this disclosure.

[0095] Figure 25 is a schematic flowchart of a first parameter adjustment method provided in some embodiments of this disclosure;

[0096] Figure 26 is a flowchart illustrating a second parameter adjustment method provided in some embodiments of this disclosure;

[0097] Figure 27 is a schematic flowchart of a second parameter adjustment method provided in some embodiments of this disclosure;

[0098] Figure 28 is a flowchart illustrating a third parameter adjustment method provided in some embodiments of this disclosure;

[0099] Figure 29 is a flowchart illustrating the third sub-parameter adjustment method provided in some embodiments of this disclosure;

[0100] Figure 30 is a flowchart illustrating a fourth sub-parameter adjustment method provided in some embodiments of this disclosure;

[0101] Figure 31 is a flowchart illustrating the air intake volume adjustment method provided in some embodiments of this disclosure;

[0102] Figure 32 is a flowchart illustrating the exhaust volume adjustment method provided in some embodiments of this disclosure;

[0103] Figure 33 is a schematic flowchart of the fourth sub-parameter adjustment method provided in some embodiments of this disclosure;

[0104] Figure 34 is a schematic flowchart of a third parameter adjustment method provided in some embodiments of this disclosure.

[0105] Figure 35 is a schematic flowchart of a third parameter adjustment method provided in some embodiments of this disclosure;

[0106] Figure 36 is a schematic flowchart of a third parameter adjustment method provided in some embodiments of this disclosure;

[0107] Figure 37 is a flowchart illustrating a fourth parameter adjustment method provided in some embodiments of this disclosure;

[0108] Figure 38 is a schematic flowchart of a fourth parameter adjustment method provided in some embodiments of this disclosure;

[0109] Figure 39 is a schematic flowchart of a drying parameter adjustment method provided in some embodiments of this disclosure;

[0110] Figure 40 is a schematic flowchart of a drying parameter adjustment method provided in some embodiments of this disclosure;

[0111] Figure 41 is a schematic flowchart of a method for drying the electrode sheet in the next step according to some embodiments of this disclosure;

[0112] Figure 42 is a schematic diagram of the control panel of an oven provided in some embodiments of this disclosure.

[0113] Figure reference numerals: 100 Electrode; 1 Drying equipment; 20 Drying area; 2 Control equipment; 3 Drying device; 3a First drying device; 3b Second drying device; 300 Control panel; 31 Oven; 310 First air inlet temperature measuring device; 311 Cabinet; 3111 Fresh air inlet; 3112 Exhaust outlet; 3113 First cabinet shell; 3114 Second cabinet shell; 3115 Second return air duct; 31150 Second return air outlet; 3116 First return air duct; 31160 First return air outlet; 3117 First air inlet duct; 3118 Second air inlet duct; 31 2 First air box; 3121 First box wall; 3122 First air inlet; 313 Air outlet velocity measuring device; 314 First air nozzle; 315 Heating device; 316 First air inlet valve; 317 First air inlet velocity measuring device; 318 Circulating fan; 319 Fresh air fan; 320 Fresh air valve; 321 Fresh air velocity measuring device; 322 Exhaust fan; 323 Exhaust valve; 324 Exhaust velocity measuring device; 325 NMP concentration measuring device; 326 Air pressure detection device; 327 Visual inspection device; 328 Second air box; 3291 Second air nozzle; 329 2 Second air inlet; 3293 Second air inlet valve; 3294 Second air inlet velocity measuring device; 330 Return air temperature measuring device; 340 Return air nozzle; 33 Fresh air main duct; 331 Main fresh air fan; 332 Main fresh air velocity measuring device; 333 Main fresh air NMP concentration measuring device; 34 Exhaust main duct; 341 Main exhaust fan; 342 Main exhaust velocity measuring device; 343 Main exhaust NMP concentration measuring device; 344 Main pressure measuring device; 39 NMP recovery system; 350 Heat exchanger; 351 Thermal oil flow meter; 352 Thermocouple; 353 Filter ; 360 Connecting assembly; 370 Air box inlet speed measuring device; 41 Unwinding unit; 42 Roller assembly; 43 Unwinding correction; 44a First coating head; 44b Second coating head; 45 First correction unit; 46 First traction unit; 47 First surface density measurement system; 48 First traction correction unit; 51 Intelligent control closed-loop system; 52 Climbing mechanism; 53 Second correction unit; 54 Second traction unit; 55 Additional drying device; 56 Cooling traction unit; 57 Second surface density measurement system; 58 Rewinding correction unit; 59 Rewinding unit. Detailed Implementation

[0114] The embodiments of the technical solutions disclosed herein will now be described in detail with reference to the accompanying drawings. These embodiments are merely illustrative of the technical solutions disclosed herein and are therefore intended to limit the scope of protection of this disclosure.

[0115] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit this disclosure; the terms “comprising” and “having”, and any variations thereof, in the specification and the foregoing description of the drawings are intended to cover non-exclusive inclusion.

[0116] In the description of the embodiments of this disclosure, technical terms such as "first," "second," and "third" are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary or secondary relationship of the indicated technical features. In the description of the embodiments of this disclosure, "a plurality of" means two or more, unless otherwise explicitly defined.

[0117] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this disclosure. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0118] In the description of the embodiments of this disclosure, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, the character " / " in this document generally indicates that the preceding and following related objects are in an "or" relationship.

[0119] In the description of the embodiments of this disclosure, the technical terms "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "circumferential," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of this disclosure and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, be constructed, operated, or used in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this disclosure.

[0120] In the description of the embodiments of this disclosure, unless otherwise expressly specified and limited, technical terms such as "installation," "connection," "joining," and "fixing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in the embodiments of this disclosure according to the specific circumstances.

[0121] In the description of the embodiments of this disclosure, unless otherwise expressly specified and limited, the technical term "contact" should be interpreted broadly, and can be direct contact, contact through an intermediate medium layer, contact between two contacting parties with substantially no interaction force, or contact between two contacting parties with interaction force.

[0122] The following is a detailed description of this disclosure.

[0123] Currently, new energy batteries are being used more and more widely in daily life and industry. They are not only used in energy storage systems for hydropower, thermal power, wind power, and solar power plants, but also extensively in electric vehicles such as electric bicycles, electric motorcycles, and electric cars, as well as in aerospace and other fields. With the continuous expansion of the application areas of power batteries, the market demand is also constantly increasing.

[0124] Lithium-ion batteries are among the most commonly used new energy batteries. They store and release electrical energy by the migration of lithium ions between the positive and negative electrodes. Lithium-ion batteries have high energy density and long cycle life, and are widely used in portable electronic devices such as mobile phones, digital cameras, and laptops. They are also widely used in large and medium-sized electric equipment such as electric vehicles, electric bicycles, and power tools. Therefore, the performance requirements for lithium-ion batteries are becoming increasingly stringent. Electrode plates are an important component of lithium-ion batteries.

[0125] In the manufacturing process of lithium-ion batteries, the electrode sheets used to make the electrode plates need to be coated first, with active materials coated on the surface of the electrode plates. Then, the coated electrode plates are dried by drying equipment. During the drying operation, factors such as the uniformity of airflow distribution, temperature uniformity, drying uniformity, and the concentration of N-methylpyrrolidone (hereinafter referred to as NMP) in the drying gas are related to the quality of the electrode plates. The quality of the electrode plates is related to the battery's capacity, energy density, cycle life, and other performance characteristics. Therefore, how to improve the manufacturing quality of electrode plates is one of the topics that the industry needs to study.

[0126] The inventors of this disclosure discovered through research that by setting an NMP concentration measuring device in the drying system to detect the NMP concentration value, the NMP concentration measuring device provides real-time feedback on the NMP concentration value. When the NMP concentration value is not within the preset range, the NMP concentration value is brought within the preset range by adjusting the amount of fresh air supplied to the drying oven and the amount of exhaust air discharged from the drying oven, thereby improving the uniformity of the drying effect and the quality of the electrode sheets.

[0127] Based on this design concept, the inventors of this disclosure have designed a drying device, which includes a fresh air main duct, an exhaust main duct, an NMP recovery system, and at least two interconnected drying ovens. Each drying oven has a drying area, and the electrode sheets are dried as they pass through the ovens. Each drying oven is equipped with a pressure detection device to detect the pressure value inside the oven as a partial pressure value. The fresh air inlets of each drying oven are connected to the fresh air main duct via pipes, and the fresh air main duct is equipped with a main fresh air fan. Each drying oven's fresh air inlet is equipped with a fresh air valve. The exhaust outlets of each drying oven are connected to the exhaust main duct via pipes, and the exhaust main duct is equipped with a main exhaust fan. Each oven has an exhaust fan and an exhaust valve at its exhaust port. N-methylpyrrolidone generated during the drying process of the NMP recovery electrode is stored in the drying area of ​​each oven. The main fresh air duct is connected to the outlet of the NMP recovery system, and the main exhaust duct is connected to the inlet of the NMP recovery system. Ovens whose partial pressure value is not in the preset negative pressure value range are designated as ovens with pressure to be adjusted. When there is at least one oven with pressure to be adjusted, the output power of the main fresh air fan and the main exhaust fan, as well as the opening of the fresh air valve and the exhaust valve of the oven with pressure to be adjusted, are adjusted so that the partial pressure value of the oven with pressure to be adjusted is in the preset negative pressure value range.

[0128] When the partial air pressure value of at least one oven is not within the preset negative pressure range, the partial air pressure values ​​of multiple ovens can be changed simultaneously by adjusting the output power of the main fresh air fan and the main exhaust fan, resulting in high adjustment efficiency. Moreover, by adjusting the opening degree of the fresh air valve and exhaust air valve of the oven to be adjusted, the amount of fresh air entering the oven and the amount of gas discharged after the drying operation can be changed. In this embodiment, the output power of the inverter of the main fresh air fan and the main exhaust fan is interlocked with the opening degree of the fresh air valve and the exhaust air valve. Through coordinated adjustment, the partial air pressure value of the oven to be adjusted is brought into the preset negative pressure range, thereby enabling the partial air pressure values ​​of each oven to quickly reach the condition of being within the preset negative pressure range. Therefore, this embodiment improves the uniformity of the drying effect, improves the quality of the electrode sheets, and has high adjustment efficiency.

[0129] The drying system provided in this disclosure can be applied, but is not limited to, the coating and drying stage in the battery electrode manufacturing process, for example, for the electrode drying stage of lithium-ion batteries. Those skilled in the art should understand that the drying system provided in this disclosure is not only used for drying electrode sheets in the battery manufacturing process, but can also be used for drying other workpieces that require drying.

[0130] The following describes some embodiments of the present disclosure in detail with reference to Figures 1 to 9.

[0131] Figure 1 is a schematic diagram of the composition of a drying system provided in some embodiments of the present disclosure; Figure 2 is a control system diagram of a drying system provided in some embodiments of the present disclosure (Figure 1); Figure 3 is a control system diagram of a drying system provided in some embodiments of the present disclosure (Figure 3); Figure 4 is a cross-sectional view of an oven provided in some embodiments of the present disclosure; Figure 5 is a simplified front view of an oven provided in some embodiments of the present disclosure; Figure 6 is a cross-sectional view along line AA in Figure 5; Figure 7 is a cross-sectional view along line BB in Figure 5; Figure 8 is a simplified top view of an oven provided in some embodiments of the present disclosure; Figure 9 is a schematic diagram of the structure of a coating machine provided in some embodiments of the present disclosure.

[0132] The first aspect of this disclosure provides a drying apparatus 3, as shown in Figures 1 to 9. The drying apparatus 3 includes a fresh air main duct 33, an exhaust main duct 34, an NMP recovery system 39, and at least two connected drying ovens 31. Each drying oven 31 has a drying area 20. The electrode 100 is dried as it passes through each drying oven 31. Each drying oven 31 has a fresh air inlet 3111 for fresh air intake and an exhaust outlet 3112 for exhausting gas from the drying oven 31. Each drying oven 31 is equipped with a pressure detection device 326, which detects the pressure value inside the drying oven 31 as a partial pressure value. The fresh air inlets 3111 of each drying oven 31 are connected to the fresh air main duct 33 via pipes. The fresh air main duct 33 is equipped with a main fresh air fan 331. Each fresh air inlet 3111 of each drying oven 31 is equipped with a fresh air valve 320. Each drying oven 31 has an exhaust outlet 3112. 112 is connected to the exhaust main duct 34 via pipelines. The exhaust main duct 34 is equipped with a main exhaust fan 341. Each oven 31 has an exhaust valve 323 at its exhaust port 3112. The NMP recovery system 39 is used to recover NMP generated during the drying process of the electrode 100 in the drying area 20 of each oven 31. The fresh air main duct 33 is connected to the outlet of the NMP recovery system 39, and the exhaust main duct 34 is connected to the inlet of the NMP recovery system 39. Ovens 31 whose partial air pressure value is not in the preset negative pressure value range are designated as ovens with pressure to be adjusted. When there is at least one oven with pressure to be adjusted, the output power of the main fresh air fan 331 and the main exhaust fan 341 and the opening degree of the fresh air valve 320 and the exhaust valve 323 of the oven with pressure to be adjusted are adjusted so that the partial air pressure value of the oven with pressure to be adjusted is in the preset negative pressure value range.

[0133] The gas discharged from the exhaust vents 3112 of each oven 31 flows into the NMP recovery system 39, which removes NMP from the gas. The removed gas is then redistributed into each oven 31 for drying. This reduces the NMP concentration in the gas within the oven 31, thereby improving the drying quality.

[0134] The main fresh air fan 331 can be a variable frequency fan, which can adjust the air frequency. This allows the main fresh air fan 331 to regulate the air velocity in the main fresh air duct 33, thereby regulating the fresh air intake velocity in each oven 31. The main exhaust fan 341 can also be a variable frequency fan, which can adjust the air frequency. This allows the main exhaust fan 341 to regulate the air velocity in the main exhaust duct 34, thereby regulating the exhaust velocity in each oven 31. Therefore, by coordinating the adjustments of the air velocities of the main fresh air fan 331 and the main exhaust fan 341, the amount of gas inside the oven 31 can be changed, thus altering the air pressure inside the oven 31.

[0135] The fresh air valve 320 can be an electrically adjustable valve. By changing the opening degree of the fresh air valve 320, the flow area of ​​the fresh air inlet 3111 can be adjusted, thereby regulating the speed at which fresh air enters the oven 31, and thus regulating the fresh air intake volume of each oven 31. The exhaust valve 323 can also be an electrically adjustable valve. By changing the opening degree of the exhaust valve 323, the flow area of ​​the exhaust outlet 3112 can be adjusted, thereby regulating the speed at which gas is discharged from the oven 31, and thus regulating the fresh air intake volume of each oven 31. By coordinating the adjustment of the opening degrees of the fresh air valve 320 and the exhaust valve 323, the gas volume in the oven 31 can be changed, thereby changing the air pressure inside the oven 31.

[0136] The air pressure detection device 326 can be a remote pressure gauge, which can remotely provide feedback on the partial air pressure value inside the oven 31. If the partial air pressure value measured by the air pressure detection device 326 is not within the preset partial negative pressure range, the output power of the frequency converters of the main fresh air fan 331 and the main exhaust fan 341, as well as the opening degree of the fresh air valve 320 and the exhaust air valve 323, are adjusted to change the partial air pressure value inside the oven 31, thereby changing the partial air pressure value to be within the preset partial negative pressure range.

[0137] When the partial air pressure value of at least one oven 31 is not within the preset negative pressure value range, the partial air pressure values ​​of multiple ovens 31 can be changed simultaneously by adjusting the output power of the main fresh air fan 331 and the main exhaust fan 341, resulting in high adjustment efficiency. Moreover, by adjusting the opening degree of the fresh air valve 320 and the exhaust air valve 323 of the oven to be adjusted, the amount of fresh air entering the oven to be adjusted and the amount of gas discharged after the drying operation can be changed. In this embodiment, the output power of the frequency converter of the main fresh air fan 331 and the main exhaust fan 341 is interlocked with the opening degree of the fresh air valve 320 and the exhaust air valve 323. Through coordinated adjustment, the partial air pressure value of the oven to be adjusted is made to be within the preset negative pressure value range, thereby enabling the partial air pressure values ​​of each oven 31 to quickly reach the condition that they are all within the preset negative pressure value range. Therefore, this embodiment improves the uniformity of the drying effect, improves the quality of the electrode sheets, and has high adjustment efficiency.

[0138] In some embodiments of this disclosure, as shown in Figures 4 to 8, each oven 31 is provided with a fresh air inlet 3111 for the intake of fresh air and an exhaust outlet 3112 for the exhaust of gas from the oven 31. Each oven 31's exhaust outlet 3112 is equipped with an NMP concentration measuring device 325, which is used to detect the NMP concentration value passing through the exhaust outlet 3112. Each oven 31 is equipped with a circulating fan 318, which drives the circulating air returning from the drying zone 20. The circulating air and the fresh air entering from the fresh air inlet 3111 flow towards the drying area 20. The oven 31 whose NMP concentration value is not in the preset NMP concentration value range is regarded as the oven to be adjusted. When there is at least one oven to be adjusted, the output power of the circulating fan 318 of the oven to be adjusted and the opening of the fresh air valve 320 and the exhaust air valve 323 are adjusted so that the NMP concentration value of the oven to be adjusted is in the preset NMP concentration value range.

[0139] The NMP concentration measuring device 325 is used to detect the concentration of N-methylpyrrolidone in the gas passing through the exhaust port 3112, and the measured concentration value is used as the NMP concentration value.

[0140] The circulating fan 318 can be a variable frequency fan, which can adjust the air frequency. By adjusting the output power of the circulating fan 318, the speed at which fresh air enters the drying oven 31 can be changed, and the speed at which the gas is discharged after the drying operation can be changed. That is, the speed at which NMP is discharged can be changed, and the NMP concentration in the gas in the drying oven 31 can be changed. Thus, by adjusting the output power of the circulating fan 318, the NMP concentration value measured by the NMP concentration measuring device 325 can be changed.

[0141] When the NMP concentration value of at least one oven 31 is not within the preset NMP concentration value range, the NMP concentration value can be changed by adjusting the output power of the circulating fan 318. The NMP concentration value can also be changed by adjusting the opening of the fresh air valve 320 and the exhaust valve 323 of the oven to be adjusted, thereby altering the amount of fresh air entering the oven and the amount of gas discharged after drying. This embodiment of the present disclosure interlocks the output power of the circulating fan 318 with the opening of the fresh air valve 320 and the exhaust valve 323, and through coordinated adjustment, ensures that the NMP concentration value of the oven to be adjusted is within the preset NMP concentration value range. This allows the NMP concentration values ​​of all ovens 31 to quickly reach the condition that they are all within the preset NMP concentration value range. Therefore, this embodiment of the present disclosure improves the uniformity of the drying effect, enhances the quality of the electrode sheets, and has high adjustment efficiency.

[0142] In some embodiments of this disclosure, as shown in FIG3, each oven 31 is provided with a wind box inlet air speed measuring device 370. The wind box inlet air speed measuring device 370 is used to detect the wind speed value of the gas after the circulating air and fresh air converge. If the wind speed value measured by the wind box inlet air speed measuring device 370 is not within the preset wind speed value range, the circulating fan 318 is adjusted so that the wind speed value measured by the wind box inlet air speed measuring device 370 is within the preset wind speed value range.

[0143] The air inlet velocity measuring device 370 can be a remote anemometer to detect the wind speed value of the gas after the circulating air and fresh air converge. After the circulating air and fresh air converge, they are immediately blown towards the drying area 20. Therefore, by ensuring that the wind speed value measured by the air inlet velocity measuring device 370 is within the preset wind speed value range, the wind speed of the gas sent to the drying area 20 is appropriate, thereby improving the uniformity of the wind speed blowing towards the electrode 100 and thus improving the quality of the electrode.

[0144] In some embodiments of this disclosure, as shown in Figures 3 and 4, each oven 31 is equipped with a fresh air fan 319 and a fresh air speed measuring device 321 at its fresh air inlet 3111. The fresh air fan 319 is used to adjust the air speed at the fresh air inlet 3111, and the fresh air speed measuring device 321 detects the air speed at the fresh air inlet 3111. Each oven 31 is equipped with an exhaust fan 322 and an exhaust speed measuring device 324 at its exhaust outlet 3112. The exhaust fan 322 is used to adjust the air speed at the exhaust outlet 3112, and the exhaust speed measuring device 324 detects the air speed at the exhaust outlet 3112.

[0145] The fresh air fan 319 can be a variable frequency fan, which can adjust the air frequency. Therefore, the air velocity entering the fresh air inlet 3111 can be adjusted by the fresh air fan 319. Thus, by adjusting the output power of the fresh air fan 319, the air volume of fresh air supplied to the oven 31 can be changed. The exhaust fan 322 can also be a variable frequency fan, which can adjust the air frequency. Therefore, the air velocity of the gas discharged from the oven 31 can be adjusted by the exhaust fan 322. Thus, by adjusting the output power of the exhaust fan 322, the air volume of the gas discharged from the oven 31 can be changed. By coordinating the adjustments of the output power of the fresh air fan 319 and the exhaust fan 322, the air volume of fresh air in the oven 31 can be changed, thereby changing the NMP concentration value of the oven 31. Furthermore, by coordinating the adjustments of the output power of the fresh air fan 319 and the exhaust fan 322, the total air volume in the oven 31 can also be changed, thereby changing the partial air pressure value of the oven 31.

[0146] The fresh air velocity measuring device 321 can be a remote-transmitting anemometer to detect the wind speed at the fresh air inlet 3111 and remotely transmit the measured wind speed value. During the adjustment of the fresh air fan 319, the wind speed value measured by the fresh air velocity measuring device 321 is referenced, allowing for more precise adjustment of the fresh air fan 319. The exhaust air velocity measuring device 324 can also be a remote-transmitting anemometer to detect the wind speed at the exhaust outlet 3112 and remotely transmit the measured wind speed value. During the adjustment of the exhaust fan 322, the wind speed value measured by the exhaust air velocity measuring device 324 is referenced, allowing for more precise adjustment of the exhaust fan 322.

[0147] Specifically, when there is at least one pressure-controlled oven, the output power of the main fresh air fan 331 and the main exhaust fan 341, the opening degree of the fresh air valve 320 and the exhaust air valve 323 of the pressure-controlled oven, and the output power of the fresh air fan 319 and the exhaust fan 322 are adjusted so that the partial pressure value of the pressure-controlled oven is within the preset partial negative pressure value range. By interlocking the main fresh air fan 331, main exhaust fan 341, fresh air valve 320, exhaust valve 323, fresh air fan 319, and exhaust fan 322, when adjustment is required, the main fresh air fan 331, main exhaust fan 341, fresh air valve 320, exhaust valve 323, fresh air fan 319, and exhaust fan 322 are adjusted according to the set interlocking rules, so that the gas pressure value of each oven 31 is within the preset negative pressure value range, thereby improving the uniformity of drying effect, improving the quality of electrode sheets, and the adjustment efficiency is high.

[0148] Specifically, when there is at least one oven with an adjustable concentration, the output power of the circulating fan 318, the opening degree of the fresh air valve 320 and the exhaust air valve 323, and the output power of the fresh air fan 319 and the exhaust fan 322 of the oven with the adjustable concentration are adjusted so that the NMP concentration value of the oven with the adjustable concentration is within a preset NMP concentration value range. Through the interlocking of the circulating fan 318, the fresh air valve 320, the exhaust air valve 323, the fresh air fan 319, and the exhaust fan 322, when adjustment is needed, the circulating fan 318, the fresh air valve 320, the exhaust air valve 323, the fresh air fan 319, and the exhaust fan 322 are adjusted according to a set interlocking rule, thereby ensuring that the NMP concentration value of each oven 31 is within the preset NMP concentration value range, thus improving the uniformity of the drying effect, improving the quality of the electrode sheets, and achieving high adjustment efficiency.

[0149] In some embodiments of this disclosure, each oven 31 is provided with a heat exchange device 350, which is used to heat the temperature of the gas after the circulating air and fresh air converge. When there is at least one oven with a concentration to be adjusted, the heating temperature of the heat exchange device 350 of the oven with the concentration to be adjusted is adjusted so that the NMP concentration value of the oven with the concentration to be adjusted is within a preset NMP concentration value range.

[0150] The heat exchanger 350 is used to heat the temperature of the gas after the confluence of circulating air and fresh air, thereby increasing the temperature of the gas blown towards the drying zone 20, thus achieving the drying of the electrode 100. The higher the drying temperature of the electrode 100, the faster the NMP is generated, resulting in a higher NMP concentration value. Therefore, by changing the heating temperature of the heat exchanger 350, the NMP concentration value can be affected, thereby keeping the NMP concentration value within a preset NMP concentration range.

[0151] The heat exchanger 350 may, but is not limited to, use a thermal oil heating device, with a thermal oil flow meter 351 and a thermocouple 352 at its oil inlet and a thermocouple 352 at its oil outlet. The heating temperature is adjusted by regulating the flow rate of hot oil entering the thermal oil heating device through the thermal oil flow meter 351.

[0152] In addition to adjusting the circulating fan 318, fresh air valve 320, exhaust air valve 323, fresh air fan 319 and exhaust fan 322, the heating temperature of the heat exchange device 350 can also be adjusted, which can accelerate the rate of NMP concentration adjustment.

[0153] In some embodiments of this disclosure, when there is at least one oven with an adjustable concentration, the output power of the main fresh air fan 331 and / or the main exhaust fan 341 is adjusted so that the NMP concentration value of the oven with the adjustable concentration is within a preset NMP concentration value range.

[0154] The main fresh air fan 331 can adjust the air velocity in the main fresh air duct 33, thereby adjusting the fresh air intake of each oven 31. Adjusting the output power of the main fresh air fan 331 will change the NMP concentration value of each oven 31. Similarly, the main exhaust fan 341 can adjust the air velocity in the main exhaust duct 34, thereby adjusting the exhaust air volume of each oven 31. Adjusting the output power of the main exhaust fan 341 will change the NMP concentration value of each oven 31.

[0155] Thus, by adjusting the circulating fan 318, fresh air valve 320, exhaust air valve 323, fresh air fan 319, exhaust fan 322 and heat exchange device 350, and by adjusting the output power of the main fresh air fan 331 and / or the main exhaust fan 341, the rate of NMP concentration adjustment can be accelerated.

[0156] In some embodiments of this disclosure, as shown in FIG3, the exhaust manifold 34 is provided with a total exhaust NMP concentration measuring device 343. The total exhaust NMP concentration measuring device 343 is used to detect the total NMP concentration value of the gas passing through the exhaust manifold 34. When there is at least one oven with an adjustable concentration and the total NMP concentration value is not within the preset total NMP concentration value range, the output power of the circulating fan 318 of the oven with the adjustable concentration and the heating temperature of the heat exchange device 350 are first adjusted to make the total NMP concentration value within the preset total NMP concentration value range. Then, the output power of the fresh air fan 319 and the exhaust fan 322 of the oven with the adjustable concentration, the opening degree of the fresh air valve 320 and the exhaust valve 323, and the heating temperature of the heat exchange device 350 are adjusted to make the NMP concentration value of the oven with the adjustable concentration within the preset NMP concentration value range.

[0157] The total exhaust NMP concentration measuring device 343 is used to detect the content of N-methylpyrrolidone in the gas in the exhaust manifold 34 as the total NMP concentration value. During adjustment, the output power of the circulating fan 318 of the oven to be adjusted and the heating temperature of the heat exchange device 350 are first adjusted so that the total NMP concentration value is within the preset total NMP concentration value range, which will make the partial NMP concentration value of the oven to be adjusted close to the preset partial NMP concentration value range. Then, the output power of the fresh air fan 319 and the exhaust fan 322 of the oven to be adjusted, the opening degree of the fresh air valve 320 and the exhaust valve 323, and the heating temperature of the heat exchange device 350 are adjusted so that the partial NMP concentration value of the oven to be adjusted is within the preset partial NMP concentration value range.

[0158] In this way, the total NMP concentration is first made to be within the preset total NMP concentration range, allowing for the simultaneous adjustment of multiple ovens with concentrations to be adjusted, which is beneficial for improving adjustment efficiency. Then, the individual NMP concentrations of the ovens with concentrations to be adjusted are made to be within the preset individual NMP concentration range, ensuring that the individual NMP concentrations of each oven 31 are within the preset individual NMP concentration range. This process of coarse adjustment followed by fine adjustment not only improves adjustment efficiency but also adjustment accuracy, thereby further enhancing the quality of the electrode sheets.

[0159] In some embodiments of this disclosure, the exhaust main duct 34 is equipped with a total pressure detection device 344. The total pressure detection device 344 is used to detect the total air pressure value in the exhaust main duct 34. When there is at least one air pressure oven to be adjusted and the total air pressure value is not in the preset total negative pressure value range, the output power of the main fresh air fan 331 and the main exhaust fan 341 is first adjusted so that the total air pressure value is in the preset total negative pressure value range. Then, the output power of the fresh air fan 319 and the exhaust fan 322 of the air pressure oven to be adjusted, as well as the opening degree of the fresh air valve 320 and the exhaust valve 323, are adjusted so that the partial air pressure value is in the preset partial negative pressure value range.

[0160] The total pressure detection device 344 can be a remote negative pressure gauge. The total pressure detection device 344 is used to detect the total air pressure value in the exhaust main pipe 34. During adjustment, the output power of the main fresh air fan 331 and the main exhaust fan 341 is first adjusted to make the total air pressure value within the preset total negative pressure value range, which will make the partial air pressure value of the air pressure oven to be adjusted close to the preset partial negative pressure value range. Then, the output power of the fresh air fan 319 and the exhaust fan 322 of the air pressure oven to be adjusted, as well as the opening degree of the fresh air valve 320 and the exhaust valve 323, are adjusted to make the partial air pressure value within the preset partial negative pressure value range.

[0161] In this way, by first ensuring that the total air pressure value is within the preset total negative pressure range, the partial air pressure values ​​of multiple air pressure ovens to be adjusted can be simultaneously affected, which is beneficial to improving the adjustment efficiency. Then, by ensuring that the partial air pressure values ​​of the air pressure ovens to be adjusted are within the preset partial air pressure range, the partial air pressure values ​​of each oven 31 are within the preset partial negative pressure range. This process of coarse adjustment followed by fine adjustment not only improves the adjustment efficiency but also the adjustment accuracy, thereby further improving the quality of the electrode sheets.

[0162] In some embodiments of this disclosure, the fresh air main duct 33 is provided with a main fresh air speed measuring device 321, which detects the air velocity of the gas in the fresh air main duct 33 during the adjustment of the main fresh air fan 331; the exhaust main duct 34 is provided with a main exhaust speed measuring device 342, which detects the air velocity of the gas in the exhaust main duct 34 during the adjustment of the main exhaust fan 341.

[0163] The main fresh air velocity measuring device 321 can be a remote-transmitting anemometer to detect the wind speed in the main fresh air duct 33 and remotely transmit the measured wind speed value. During the adjustment of the main fresh air fan 331, the wind speed value measured by the main fresh air velocity measuring device 321 is referenced, allowing for more precise adjustment of the main fresh air fan 331. The main exhaust air velocity measuring device 342 can also be a remote-transmitting anemometer to detect the wind speed in the main exhaust duct 34 and remotely transmit the measured wind speed value. During the adjustment of the main exhaust fan 341, the wind speed value measured by the main exhaust air velocity measuring device 342 is referenced, allowing for more precise adjustment of the main exhaust fan 341.

[0164] This improves the accuracy of airflow regulation in the main fresh air duct 33 and the main exhaust air duct 34, thereby improving the accuracy of air pressure regulation and NMP concentration regulation, which in turn improves the uniformity of drying effect, enhances the quality of electrode sheets, and increases regulation efficiency.

[0165] In some embodiments of this disclosure, the main fresh air duct 33 is equipped with a main fresh air NMP concentration measuring device 333, which is used to detect the NMP gas concentration in the gas within the main fresh air duct 33. The main fresh air NMP concentration measuring device 333 can assist in adjusting the N-methylpyrrolidone concentration by using the concentration value detected by the main fresh air NMP concentration measuring device 333 as a reference.

[0166] In some embodiments of this disclosure, each oven 31 includes a housing 311 and a first air box 312 and a second air box 328 disposed within the housing 311. The first air box 312 and the second air box 328 are disposed opposite to each other, and a drying area 20 is defined between them. The first air box 312 is provided with a first air inlet 3122 for gas to enter, and the second air box 328 is provided with a second air inlet 3292 for gas to enter. The first air box 312 has a first housing wall 3121 facing the second air box 328, and the first housing wall 3121 is provided with a plurality of first air nozzles 314 with outlets facing the drying area 20. The first air nozzle 314 is used to discharge the gas in the first air box 312 toward the electrode 100; the second air box 328 has multiple second air nozzles 3291 with outlets facing the drying area 20 on its box wall facing the first air box 312. The second air nozzles 3291 are used to discharge the gas in the second air box 328 toward the electrode 100. The box body 311 has a fresh air inlet 3111 and an exhaust outlet 3112. The fresh air inlet 3111 is connected to the first air inlet 3122 of the first air box 312 and the second air inlet 3292 of the second air box 328. The exhaust outlet 3112 is connected to the drying area 20.

[0167] As shown in Figures 5 to 8, arrows indicate the direction of gas flow inside the housing 311. The fresh air entering from the fresh air inlet 3111 of the housing 311 is divided into two paths. One path enters the first air box 312 through the first air inlet 3122, then enters the drying area 20 through the first air nozzle 314, blowing onto the surface of the electrode 100 coated with the active material slurry that passes through the drying area 20. The other path enters the second air box 328 through the second air inlet 3292, then enters the drying area 20 through the second air nozzle 3291, blowing onto the other surface of the electrode 100 that passes through the drying area 20, thus achieving the drying of the electrode 100.

[0168] In some embodiments of this disclosure, a return air duct is provided inside the housing 311, and a circulating fan 318 is provided inside the return air duct. The fresh air inlet 3111 and the exhaust outlet 3112 are respectively connected to the return air duct. The circulating fan 318 is used to drive the gas in the drying area 20 through the return air duct and through the exhaust outlet 3112, so that some of the gas is discharged outside through the exhaust outlet 3112, and to drive the remaining gas in the return air duct and the fresh air replenished from the fresh air inlet 3111 through the return air duct into the first air inlet 3122 and the second air inlet 3292. A heat exchange device 350, a wind box inlet speed measuring device 370 and a circulating fan 318 are provided in the channel between the fresh air inlet 3111 and the first air inlet 3122 and the second air inlet 3292.

[0169] Under the action of the circulating fan 318, the gas in the drying zone 20 circulates back along the return air channel toward the first air inlet 3122 of the first air box 312 and the second air inlet 3292 of the second air box 328. During the flow, it will pass through the exhaust port 3112 and the fresh air inlet 3111 in sequence. When passing through the exhaust port 3112, some gas will flow through the exhaust port 3112 along the pipeline to the exhaust main duct 34. The remaining gas in the return air channel continues to circulate back along the first air inlet 3122 and the second air inlet 3292 as circulating air. When the circulating air passes through the fresh air inlet 3111, the fresh air added through the fresh air inlet 3111 will merge with the circulating air. The merged gas is heated by the heat exchange device 350 to form hot air. Then the hot air enters the first air box 312 and the second air box 328 respectively, and then enters the drying zone 20 for drying.

[0170] The gas flowing in the return air duct from the fresh air inlet 3111 to the first air box 312 and the second air box 328 is the gas formed by the convergence of fresh air and circulating air. A heat exchange device 350 is installed at this location. The heat exchange device 350 can heat the temperature of the gas formed by the convergence of fresh air and circulating air. The heating temperature of the heat exchange device 350 is directly related to the temperature of the gas blown into the drying area 20 by the first air nozzle 314 of the first air box 312 and the second air nozzle 3291 of the second air box 328. Therefore, by adjusting the heating temperature of the heat exchange device 350, the temperature of the gas sent to the drying area 20 can be made suitable, so that the amount of N-methylpyrrolidone produced during drying is within a suitable range, thereby improving the quality of the electrode sheet.

[0171] In this way, some of the gas in the drying zone 20 can re-enter the first air box 312 and the second air box 328 through the return air channel, and then be blown to the electrode 100, thus recycling the gas. The recycled gas also has high heat, which helps to reduce heat loss and improve heat utilization.

[0172] In some embodiments of this disclosure, a heating device 315 is provided on the outer side of the first box wall 3121.

[0173] The heating device 315 inside the oven 31 heats the gas in the drying zone 20, thereby drying the electrode 100 passing through the drying zone 20. Simultaneously, the gas in the first air box 312 is blown onto the passing electrode 100 through the first air nozzle 314, promoting the drying efficiency of the electrode 100. The first air nozzles 314 are evenly distributed on the first oven wall 3121, which helps improve the uniformity of the drying effect and further improves the quality of the electrode.

[0174] The heating device 315 is a device for heating the gas in the drying zone 20, and can be, but is not limited to, a resistance heat exchanger or an infrared heat exchanger.

[0175] A resistance heat exchanger is a device that heats an object by the heat generated by the Joule effect when an electric current flows through it.

[0176] Infrared heat exchangers primarily heat air through point-to-point thermal radiation (principle: when the vibrational or rotational amplitude of molecular groups is close to the infrared wavelength amplitude, energy level transitions occur, increasing molecular motion and raising temperature). When applying reflective coatings, thick coatings, or metallic coatings, they offer rapid preheating and even shorter heating times, reaching the set temperature quickly. They also boast stronger penetration and higher drying efficiency, enabling rapid drying of the inner and middle layers of the electrode coating.

[0177] In this way, the drying effect of the electrode 100 after passing through the drying zone 20 is achieved, and the drying uniformity is high, resulting in high quality of the electrode.

[0178] In some embodiments of this disclosure, a first air inlet valve 316 is provided at the first air inlet 3122 of the first air box 312, and a second air inlet valve 3293 is provided at the second air inlet 3292 of the second air box 328. During the process of adjusting the output power of the circulating fan 318, the opening degree of the first air inlet valve 316 and / or the second air inlet valve 3293 is adjusted.

[0179] The first air inlet valve 316 can be an electric regulating valve. By adjusting the opening of the first air inlet valve 316, the flow area of ​​the first air inlet 3122 can be adjusted, thereby adjusting the speed at which gas enters the first air box 312. This affects the wind speed of the gas blown into the drying area 20 by the first air nozzle 314. Therefore, during the process of adjusting the output power of the circulating fan 318, the wind speed blown towards the electrode 100 can be controlled within a suitable range by adjusting the first air inlet valve 316, thereby improving the uniformity of drying and resulting in high-quality electrode sheets.

[0180] The second air inlet valve 3293 can be an electric regulating valve. By adjusting the opening of the second air inlet valve 3293, the flow area of ​​the second air inlet 3292 can be adjusted, thereby adjusting the speed at which gas enters the second air box 328. This affects the wind speed of the gas blown into the drying area 20 by the second air nozzle 3291. Therefore, during the process of adjusting the output power of the circulating fan 318, the wind speed blown onto the electrode 100 can be controlled within a suitable range by adjusting the opening of the second air inlet valve 3293, thereby improving the uniformity of drying and resulting in high-quality electrode sheets.

[0181] In some embodiments of this disclosure, a first air inlet temperature measuring device 310 is provided at the first air inlet 3122 of the first air box 312. The first air inlet temperature measuring device 310 is used to detect the temperature of the gas passing through the first air inlet 3122. A second air inlet temperature measuring device is provided at the second air inlet 3292 of the second air box 328, and the second air inlet temperature measuring device is used to detect the temperature of the gas passing through the second air inlet 3292. The first air inlet temperature measuring device 310 and the second air inlet temperature measuring device can be, but are not limited to, temperature sensors. When adjusting the air pressure or NMP gas concentration inside the drying oven 31, the drying device can use the temperatures detected by the first air inlet temperature measuring device 310 and / or the second air inlet temperature measuring device as a reference to assist in the adjustment.

[0182] In some embodiments of this disclosure, a first air inlet speed measuring device 317 is provided at the first air inlet 3122 of the first air box 312, and a second air inlet speed measuring device 3294 is provided at the second air inlet 3292 of the second air box 328.

[0183] The first air inlet velocity measuring device 317 can be a remote anemometer to detect the air velocity of the gas passing through the first air inlet 3122. The second air inlet velocity measuring device 3294 can also be a remote anemometer to detect the air velocity of the gas passing through the second air inlet 3292. When adjusting the air pressure or N-methylpyrrolidone gas concentration inside the drying oven 31, the drying device can use the air velocities detected by the first and second air inlet velocity measuring devices 317 and 3294 as references to assist in the adjustment, which helps to improve the uniformity of the drying effect and the quality of the electrode sheets.

[0184] In some embodiments of this disclosure, as shown in Figures 5 to 8, the housing 311 includes a first housing 3113, a second housing 3114, a first air inlet pipe 3117, and a first air return pipe 3116. A fresh air inlet 3111 and an exhaust outlet 3112 are respectively located on the top wall of the second housing 3114. A circulating fan 318 is located on the side wall of the second housing 3114. A first air box 312 is located inside the first housing 3113. The first air inlet pipe 3117 connects the first air inlet 3122 of the first air box 312 inside the first housing 3113 with the second housing 3114. The first air return pipe 3116 connects the area defined between the outer wall of the first air box 312 and the inner wall of the first housing 3113 inside the first housing 3113 with the second housing 3114. The opening of the end of the first air return pipe 3116 that extends into the first housing 3113 is the first air return outlet 31160. The second air box 328 is located inside the first housing 3113. The second air inlet 3292 of the second air box 328 inside the first housing 3113 is connected to the second housing 3114 through the second air inlet pipe 3118. The area between the second air box 328 inside the first housing 3113 and the inner wall of the first housing 3113 (excluding the wall facing the drying area 20) is connected to the second housing 3114 through the second return air pipe 3115. The opening of the end of the second return air pipe 3115 that extends into the first housing 3113 is the second return air inlet 31150.

[0185] Fresh air enters the second housing 3114 through the fresh air inlet 3111, then enters the first air box 312 through the first air inlet duct 3117. The gas in the first air box 312 then enters the drying area 20 through the first air nozzle 314 and is blown toward the electrode 100. After that, the gas in the drying area 20 flows out of the drying area 20 along the conveying path of the electrode 100, and then enters the first return air duct 3116 along the area between the other walls of the first air box 312 (excluding the first box wall 3121) and the inner wall of the first housing 3113. After that, it flows back into the second housing 3114 through the first return air duct 3116. Some of the gas in the second housing 3114 re-enters the first air inlet duct 3117 for the aforementioned circulation, while the other part of the gas in the second housing 3114 exits through the exhaust port 3112. It is understandable that the gas entering the first air inlet duct 3117 includes the gas flowing back from the first return air duct 3116 and the fresh air supplied from the fresh air inlet 3111.

[0186] Fresh air enters the second housing 3114 through the fresh air inlet 3111. Then, some of the gas in the second housing 3114 enters the second air box 328 through the second air inlet 3118. Next, the gas in the second air box 328 enters the drying area 20 through the second air nozzle 3291 and is blown towards the electrode 100. Afterward, the gas in the drying area 20 flows out along the conveying path of the electrode 100. Then, some of the gas flows along the area between the second air box 328 (excluding the wall facing the drying area 20) and the inner wall of the first housing 3113, entering the second return air duct 3115. Afterward, it flows back to the second housing 3114 through the second return air duct 3115. Some of the gas in the second housing 3114 re-enters the second air inlet 3118 for the aforementioned circulation. The remaining gas in the second housing 3114 exits through the exhaust port 3112. It is understandable that during the gas flow through the second air box 328, the gas flow through the first air box 312 is also occurring simultaneously. Therefore, the gas entering the second air box 328 through the second air inlet duct 3118 includes the gas flowing back from the first return air duct 3116, the gas flowing back from the second return air duct 3115, and the fresh air supplied from the fresh air inlet 3111. Similarly, the gas entering the first air box 312 through the first air inlet duct 3117 includes the gas flowing back from the first return air duct 3116, the gas flowing back from the second return air duct 3115, and the fresh air supplied from the fresh air inlet 3111.

[0187] It should be noted that the return air duct includes the space inside the second housing 3114, the first air inlet duct 3117, the area defined between the other walls of the first air box 312 inside the first housing 3113 (excluding the first housing wall 3121) and the inner wall of the first housing 3113, and the first return air duct 3116. The return air duct also includes the space inside the second air inlet duct 3118, the area defined between the other walls of the second air box 328 inside the first housing 3113 (excluding the housing wall facing the drying area 20) and the inner wall of the first housing 3113, and the second return air duct 3115.

[0188] In some embodiments of this disclosure, the first air box 312 and the second air box 328 are distributed along the vertical direction Z, and the first air box 312 is located above the second air box 328. The second air nozzle 3291 on the second air box 328 supports the electrode 100 located in the drying area 20.

[0189] Specifically, the first housing 3113 and the second housing 3114 are spaced apart in the first direction Y. The first air inlet duct 3117 and the first air return duct 3116 extend along the first direction Y and are distributed along the second direction X. Both the first direction Y and the second direction X intersect the vertical direction Z, including perpendicular intersections. The fresh air inlet 3111 and the exhaust air outlet 3112 are located at the top of the second housing 3114. The circulating fan 318 is located on the side wall of the second housing 3114 away from the first housing 3113. The drying area 20 is located along the second direction X.

[0190] In some embodiments of this disclosure, the first chamber wall 3121 is provided with a return air nozzle 340 for the return air channel to allow the gas in the drying area 20 to flow back to the return air channel.

[0191] Specifically, the return air nozzle 340 connects to the area defined between the other walls of the first air box 312 inside the first housing 3113 (excluding the first housing wall 3121) and the inner wall of the first housing 3113.

[0192] The gas in the drying zone 20 can enter the return air channel through the return air nozzle 340 located on the first box wall 3121. This shortens the gas flow path, reduces the resistance along the circulation process and the wind speed fluctuation, improves the uniformity of the lateral air volume, and enables the uniform drying of the coating "surface" of the electrode 100, thereby achieving uniform drying of the thick coating inner and outer layers, improving lateral cracking and excessive edge drying, and thus improving the quality of the electrode.

[0193] Specifically, the air pressure detection device 326 is located in the area between the side of the first air box 312 of the housing 311 away from the drying area 20 and the inner wall of the housing 311.

[0194] In some embodiments of this disclosure, a visual inspection device 327 is provided on the outer side of the first box wall 3121 of the first air box 312. The visual inspection device 327 is used to inspect the appearance of the electrode 100 located in the drying area 20.

[0195] The visual inspection device 327 can be an AI visual inspection device, which can monitor the appearance of the electrode 100 inside the drying area 20 online. When the appearance of the electrode 100 is abnormal, the drying data can be corrected in time by controlling and adjusting the wind speed, negative pressure or NMP concentration, thereby improving the coating drying quality and efficiency.

[0196] In some embodiments of this disclosure, the visual inspection device 327 is connected to the outside of the first housing wall 3121 by a mounting assembly, the mounting assembly being configured to adjust the position of the visual inspection device 327 along the width direction of the electrode 100.

[0197] For example, the vision inspection device 327 can be reciprocated along the width direction of the electrode 100 via a lead screw and nut assembly. Of course, the position of the vision inspection device 327 can also be adjusted via other linear drive devices, which will not be elaborated here.

[0198] This allows for a wider inspection of the appearance of the electrode 100, further improving the quality and efficiency of coating and drying.

[0199] In some embodiments of this disclosure, as shown in FIG8, a filter 353 is provided outside the inlet of the second housing 3114 near the inlet of the first air inlet pipe 3117 and the inlet of the second air inlet pipe 3118, and a heat exchange device 350 is provided on the side of the filter 353 away from the inlet of the first air inlet pipe 3117 and the inlet of the second air inlet pipe 3118.

[0200] The filter 353 can filter and purify the passing gas, and the heat exchange device 350 is used to exchange heat with the passing gas to heat the gas, so that the heated gas blows onto the electrode 100 to dry the electrode 100.

[0201] The heat exchanger 350 may, but is not limited to, use a thermal oil heating device, with a thermal oil flow meter 351 and a thermocouple 352 at its oil inlet. The heating temperature is adjusted by regulating the flow rate of hot oil entering the thermal oil heating device through the thermal oil flow meter 351.

[0202] In some embodiments of this disclosure, the first bellows 312 and the second bellows 328 are respectively connected to the top wall and bottom wall of the first housing 3113 via a connecting component 360. The connecting component 360 is configured to adjust the position of the first bellows 312 and / or the second bellows 328 along the vertical direction Z.

[0203] Thus, the distance between the first air box 312 and the second air box 328 can be adjusted by connecting component 360, which means adjusting the size of the drying area 20 in the vertical Z direction. This reduces the distance between the electrode 100 and the air outlet velocity measuring device, air inlet velocity measuring device 370, first air nozzle 314, and heating device 315 located on the first box wall 3121. The drying efficiency can be improved by adjusting the distance. With the same length of oven arrangement, this high-efficiency drying device can save energy and reduce the number of oven sections, thereby saving development costs.

[0204] For example, the connecting component 360 can be a linear drive mechanism such as an adjusting screw, a linear motor, or a cylinder, which enables the installation of the first air box 312 and the second air box 328 within the first housing 3113 and allows adjustment of the position of the first air box 312 and the second air box 328 along the vertical direction Z.

[0205] A second aspect of this disclosure provides a coating machine comprising a first coating head 44a, a second coating head 44b, a climbing mechanism 52, and a first drying device 3a and a second drying device 3b formed by the aforementioned drying device. The first coating head 44a is used to coat a first surface of a substrate to form an electrode 100. The first drying device 3a is located downstream of the first coating head 44a and is used to dry the electrode 100 with its first surface facing upward. The second coating head 44b is located downstream of the first drying device 3a and is used to coat a second surface of the electrode 100. The climbing mechanism 52 is located downstream of the second coating head 44b and upstream of the second drying device 3b. The climbing mechanism 52 is used to support the electrode 100 from one side of the first surface of the electrode 100 and to pull the electrode 100 so that the electrode 100 enters the second drying device 3b with its second surface facing upward. The second drying device 3b is used to dry the electrode 100 with its second surface facing upward.

[0206] The electrode 100 has two sides, designated as a first side and a second side. A first coating head 44a coats the first side of the electrode 100, and then a first drying device 3a dries the electrode 100 conveyed from the first coating head 44a. A second coating head 44b coats the second side of the electrode 100, and then a second drying device 3b dries the electrode 100 conveyed from the second coating head 44b. This completes the coating and drying process for both sides of the electrode 100.

[0207] The first coating head 44a, the first drying device 3a, and the second coating head 44b are arranged in the lower row. The surface to be dried in the first drying device 3a is the first surface, which faces upward. The climbing mechanism 52 and the second drying device 3b are arranged in the upper row. The electrode 100 is folded upward by the climbing mechanism 52, so that the second surface that was originally output from the first drying device 3a facing downward is folded upward. That is, the second surface that needs to be dried by the second drying device 3b faces upward. The surfaces to be dried in the first drying device 3a and the second drying device 3b are both facing upward, so that the other surface contacts the second air nozzle 3291 of the drying device. The electrode 100 is supported by the second air nozzle 3291, and the surface to be dried does not contact the first air nozzle 314, thus adjusting the drying effect.

[0208] In some embodiments of this disclosure, as shown in FIG9, the coating machine includes an unwinding unit 41, a roller assembly 42, an unwinding correction unit 43, a first coating head 44a, a first drying device 3a, a first correction unit 45, a first traction unit 46, a first surface density measurement system 47, a first traction correction unit 48, a second coating head 44b, a climbing mechanism 52, a second drying device 3b, a second correction unit 53, a second traction unit 54, an auxiliary drying device 55, a cooling traction unit 56, a second surface density measurement system 57, a winding correction unit 58, and a winding unit 59, arranged sequentially. The unwinding unit 41 is used for automatic unwinding and conveying of the electrode sheet 100; the roller assembly 42 provides support for the conveying of the electrode sheet 100; the unwinding correction unit 43 centers the electrode sheet 100 on the conveying; the first coating head 44a is used for coating the first side of the electrode sheet 100; the first drying device 3a is used for the first drying of the electrode sheet 100; the first correction unit 45 centers the electrode sheet 100 and also flattens and removes wrinkles; the first traction unit 46 provides traction and tension interruption during the conveying process of the electrode sheet 100 to ensure balanced conveying tension; the first surface density measurement system 47 monitors the density of the first coated surface in real time; the first traction correction unit 48 centers the electrode sheet 100; the second coating head 44b coats the second side of the electrode sheet 100; and the climbing mechanism 52 enables the electrode sheet 100 to be automatically unwound and conveyed. The first drying unit 50 ensures the stability of the electrode 100; the second drying unit 3b is used for the second drying of the electrode 100; the second correction unit 53 is used to center the electrode 100 and also to flatten and remove wrinkles from the electrode 100; the second traction unit 54 realizes traction and tension interruption during the electrode 100's movement, ensuring balanced tension; the additional drying unit 55 performs a third drying of the electrode 100 to improve the electrode's process performance; the cooling traction unit 56 realizes the traction and cooling of the film formed by the electrode 100, ensuring that the film does not wrinkle during movement; the second surface density measurement system 57 realizes real-time monitoring of the surface density of the coating on the first and second surfaces; the winding correction unit 58 realizes the centering of the film before winding; the winding unit 59 realizes the automatic winding and automatic roll changing of the film.

[0209] Specifically, the coating machine also includes an intelligent control closed-loop system 51, which is used for closed-loop control and adjustment of the entire coating machine.

[0210] The third aspect of this disclosure provides a drying method using a drying apparatus 3. An oven 31 has a drying zone 20. The electrode 100 is dried as it passes through each oven 31. Each oven 31 has a fresh air inlet 3111 for introducing fresh air and an exhaust outlet 3112 for discharging gas from the oven 31. Each oven 31 is equipped with a pressure detection device 326, which detects the pressure value inside the oven 31 as a partial pressure value. The fresh air inlets 3111 of each oven 31 are connected to a main fresh air duct 33 via pipes. The main fresh air duct 33 has a main... A fresh air fan 331 is provided, and a fresh air valve 320 is provided at the fresh air inlet 3111 of each oven 31; the exhaust outlet 3112 of each oven 31 is connected to the exhaust main duct 34 through pipelines, and the exhaust main duct 34 is provided with a main exhaust fan 341, and an exhaust valve 323 is provided at the exhaust outlet 3112 of each oven 31; the NMP recovery system 39 is used to recover the NMP generated by the electrode 100 in the drying area 20 of each oven 31 during the drying process, the fresh air main duct 33 is connected to the outlet of the NMP recovery system 39, and the exhaust main duct 34 is connected to the inlet of the NMP recovery system 39.

[0211] As shown in Figure 10, the drying method includes:

[0212] S1000, Air pressure adjustment step: The oven whose partial air pressure value measured by the air pressure detection device is not in the preset partial negative pressure value range is regarded as the air pressure oven to be adjusted. When there is at least one air pressure oven to be adjusted, the output power of the main fresh air fan and the main exhaust fan and the opening degree of the fresh air valve and exhaust air valve of the air pressure oven to be adjusted are adjusted so that the partial air pressure value of the air pressure oven to be adjusted is in the preset partial negative pressure value range.

[0213] When the partial air pressure value of at least one oven 31 is not within the preset negative pressure value range, the partial air pressure values ​​of multiple ovens 31 can be changed simultaneously by adjusting the output power of the main fresh air fan 331 and the main exhaust fan 341, resulting in high adjustment efficiency. Moreover, by adjusting the opening degree of the fresh air valve 320 and the exhaust air valve 323 of the oven to be adjusted, the amount of fresh air entering the oven to be adjusted and the amount of gas discharged after the drying operation can be changed. In this embodiment, the output power of the frequency converter of the main fresh air fan 331 and the main exhaust fan 341 is interlocked with the opening degree of the fresh air valve 320 and the exhaust air valve 323. Through coordinated adjustment, the partial air pressure value of the oven to be adjusted is made to be within the preset negative pressure value range, thereby enabling the partial air pressure values ​​of each oven 31 to quickly reach the condition that they are all within the preset negative pressure value range. Therefore, this embodiment improves the uniformity of the drying effect, improves the quality of the electrode sheets, and has high adjustment efficiency.

[0214] In some embodiments of this disclosure, each oven 31 is provided with a circulating fan 318, which drives the gas after the circulating air returning from the drying area 20 and the fresh air entering from the fresh air inlet to flow toward the drying area 20; each oven 31 is provided with a wind box inlet air speed measuring device 370, which is used to detect the wind speed value of the gas after the circulating air and the fresh air converge.

[0215] As shown in Figure 11, the drying method includes the following steps after the air pressure regulation step:

[0216] S2000, wind speed adjustment steps: If the wind speed value measured by the wind box inlet air speed measuring device is not within the preset wind speed value range, adjust the circulating fan so that the wind speed value measured by the wind box inlet air speed measuring device is within the preset wind speed value range.

[0217] The air inlet velocity measuring device 370 can be a remote anemometer to detect the wind speed value of the gas after the circulating air and fresh air converge. After the circulating air and fresh air converge, they are immediately blown towards the drying area 20. Therefore, by ensuring that the wind speed value measured by the air inlet velocity measuring device 370 is within the preset wind speed value range, the wind speed of the gas sent to the drying area 20 is appropriate, thereby improving the uniformity of the wind speed blowing towards the electrode 100 and thus improving the quality of the electrode.

[0218] In some embodiments of this disclosure, each oven is equipped with an NMP concentration measuring device 325 at its exhaust vent. The NMP concentration measuring device 325 is used to detect the NMP concentration value passing through the exhaust vent 3112.

[0219] As shown in Figure 12, the drying method includes the following steps after the air speed adjustment step:

[0220] S3000, Concentration Adjustment Step: The oven whose NMP concentration value measured by the NMP concentration measuring device is not within the preset NMP concentration value range is taken as the oven to be adjusted. If there is at least one oven to be adjusted, the output power of the circulating fan and the opening of the fresh air valve and the exhaust air valve of the oven to be adjusted are adjusted so that the NMP concentration value of the oven to be adjusted is within the preset NMP concentration value range.

[0221] When the NMP concentration value of at least one oven 31 is not within the preset NMP concentration value range, the NMP concentration value can be changed by adjusting the output power of the circulating fan 318. The NMP concentration value can also be changed by adjusting the opening of the fresh air valve 320 and the exhaust valve 323 of the oven to be adjusted, thereby altering the amount of fresh air entering the oven and the amount of gas discharged after drying. This embodiment of the present disclosure interlocks the output power of the circulating fan 318 with the opening of the fresh air valve 320 and the exhaust valve 323, and through coordinated adjustment, ensures that the NMP concentration value of the oven to be adjusted is within the preset NMP concentration value range. This allows the NMP concentration values ​​of all ovens 31 to quickly reach the condition that they are all within the preset NMP concentration value range. Therefore, this embodiment of the present disclosure improves the uniformity of the drying effect, enhances the quality of the electrode sheets, and has high adjustment efficiency.

[0222] In some embodiments of this disclosure, each oven 31 is provided with a fresh air fan 319 at its fresh air inlet 3111, and the fresh air fan 319 is used to adjust the air speed of the fresh air inlet 3111; each oven 31 is provided with an exhaust fan 322 at its exhaust outlet 3112, and the exhaust fan 322 is used to adjust the air speed of the exhaust outlet 3112.

[0223] In the air pressure regulation step, the output power of the fresh air fan 319 and the exhaust fan 322 of the oven to be regulated are also adjusted.

[0224] In the concentration adjustment step, the output power of the fresh air fan 319 and the exhaust fan 322 of the oven to be adjusted are also adjusted.

[0225] By adjusting the output power of the fresh air fan 319 and the exhaust fan 322, the air volume of the fresh air in the oven 31 can be changed, thereby changing the NMP concentration value of the oven 31. Furthermore, by adjusting the output power of the fresh air fan 319 and the exhaust fan 322, the total air volume in the oven 31 can also be changed, thereby changing the gas pressure value of the oven 31.

[0226] In some embodiments of this disclosure, each oven 31 is provided with a heat exchange device 350, which is used to heat the temperature of the gas after the circulating air and fresh air converge.

[0227] In the concentration adjustment step, the heating temperature of the heat exchange device 350 of the oven to be adjusted is also adjusted.

[0228] The heat exchanger 350 is used to heat the temperature of the gas after the confluence of circulating air and fresh air, thereby increasing the temperature of the gas blown towards the drying zone 20, thus achieving the drying of the electrode 100. The higher the drying temperature of the electrode 100, the faster the NMP is generated, resulting in a higher NMP concentration value. Therefore, by changing the heating temperature of the heat exchanger 350, the NMP concentration value can be affected, thereby keeping the NMP concentration value within a preset NMP concentration range.

[0229] In some embodiments of this disclosure, the output power of the main fresh air fan 331 and / or the main exhaust fan 341 is also adjusted during the concentration adjustment step.

[0230] Thus, by adjusting the circulating fan 318, fresh air valve 320, exhaust air valve 323, fresh air fan 319, exhaust fan 322 and heat exchange device 350, and by adjusting the output power of the main fresh air fan 331 and / or the main exhaust fan 341, the rate of NMP concentration adjustment can be accelerated.

[0231] In some embodiments of this disclosure, the exhaust manifold is equipped with a total exhaust NMP concentration measuring device 343, which is used to detect the total NMP concentration value of the gas passing through the exhaust manifold 34.

[0232] As shown in Figure 13, the concentration adjustment steps include:

[0233] S301, Total concentration adjustment step: When there is at least one oven with a concentration to be adjusted and the total NMP concentration value is not within the preset total NMP concentration value range, adjust the output power of the circulating fan of the oven with the concentration to be adjusted and the heating temperature of the heat exchange device so that the total NMP concentration value is within the preset total NMP concentration value range.

[0234] S302, concentration adjustment step: adjust the output power of the fresh air fan and exhaust fan of the oven to be adjusted, the opening degree of the fresh air valve and exhaust air valve, and the heating temperature of the heat exchange device so that the NMP concentration value of the oven to be adjusted is within the preset NMP concentration value range.

[0235] In this way, the total NMP concentration is first made to be within the preset total NMP concentration range, allowing for the simultaneous adjustment of multiple ovens with concentrations to be adjusted, which is beneficial for improving adjustment efficiency. Then, the individual NMP concentrations of the ovens with concentrations to be adjusted are made to be within the preset individual NMP concentration range, ensuring that the individual NMP concentrations of each oven 31 are within the preset individual NMP concentration range. This process of coarse adjustment followed by fine adjustment not only improves adjustment efficiency but also adjustment accuracy, thereby further enhancing the quality of the electrode sheets.

[0236] In some embodiments of this disclosure, the exhaust main duct 34 is provided with a total pressure detection device 344, which is used to detect the total air pressure value in the exhaust main duct 34.

[0237] As shown in Figure 14, the air pressure regulation steps include:

[0238] S101, Total air pressure adjustment step: When there is at least one oven with air pressure to be adjusted and the total air pressure value is not within the preset total negative pressure value range, adjust the output power of the main fresh air fan and the main exhaust fan so that the total air pressure value is within the preset total negative pressure value range.

[0239] S102, Partial air pressure adjustment step: Adjust the output power of the fresh air fan and exhaust fan of the air pressure oven to be adjusted, and the opening degree of the fresh air valve and exhaust air valve, so that the partial air pressure value is within the preset partial negative pressure value range.

[0240] In this way, by first ensuring that the total air pressure value is within the preset total negative pressure range, the partial air pressure values ​​of multiple air pressure ovens to be adjusted can be simultaneously affected, which is beneficial to improving the adjustment efficiency. Then, by ensuring that the partial air pressure values ​​of the air pressure ovens to be adjusted are within the preset partial air pressure range, the partial air pressure values ​​of each oven 31 are within the preset partial negative pressure range. This process of coarse adjustment followed by fine adjustment not only improves the adjustment efficiency but also the adjustment accuracy, thereby further improving the quality of the electrode sheets.

[0241] In some embodiments of this disclosure, each oven's drying area is provided with a visual inspection device 327, which is used to inspect the appearance of the electrode 100 passing through the drying area 20.

[0242] As shown in Figure 15, the drying method also includes:

[0243] S4000, Visual Feedback Step: If the appearance measured by the visual inspection device does not conform to the preset appearance reference standard, perform an air pressure adjustment step, and / or a wind speed adjustment step, and / or a concentration adjustment step.

[0244] The visual inspection device 327 can monitor the appearance of the electrode 100 inside the drying zone 20 online. When the appearance of the electrode 100 is abnormal, the drying data can be corrected in time by controlling and adjusting the wind speed, negative pressure or NMP concentration, thereby improving the coating drying quality and efficiency.

[0245] In some embodiments of this disclosure, as shown in FIG16, the drying method further includes:

[0246] The S5000 obtains the final drying parameters after the drying process of a batch of electrodes has been completed.

[0247] The final drying parameters include the final output power of the main fresh air fan and the main exhaust fan, and the final opening degree of the fresh air valve and the exhaust air valve of the pressure-controlled oven to be adjusted. When the drying process of the next batch of electrode sheets begins, the drying device dries the next batch of electrode sheets according to the final drying parameters.

[0248] In this way, after the drying device is debugged for the first batch of electrode sheets 100, it can obtain stable final drying parameters and then directly apply the final drying parameters to the next batch of electrode sheets 100. Based on this, the drying process for the same electrode sheets 100 can be completed with one debugging, avoiding the technical problem in the prior art that the drying situation needs to be manually observed and the drying equipment adjusted for each drying process of electrode sheets 100, thereby reducing labor costs and electrode scrap costs.

[0249] The fourth aspect of the application provides a drying method applied to a drying system. Referring to Figures 1 and 9, the drying system includes a drying device 1 and a control device 2. The drying device 1 includes a first drying device 3a and a second drying device 3b formed by the drying device 3 provided in the first aspect. The control device 2 is used to control the drying device 1 to perform drying operations.

[0250] The first NMP concentration value in the following content corresponds to the total NMP concentration value in the above content, and the first preset NMP concentration value range in the following content corresponds to the preset total NMP concentration value range in the above content. The second NMP concentration value in the following content corresponds to the partial NMP concentration value in the above content, and the second preset NMP concentration value range in the following content corresponds to the preset partial NMP concentration value range in the above content. The first negative pressure value in the following content corresponds to the total air pressure value in the above content, and the first preset negative pressure value range in the following content corresponds to the preset total negative pressure value range in the above content. The second negative pressure value in the following content corresponds to the partial air pressure value in the above content, and the second preset negative pressure value range in the following content corresponds to the preset partial negative pressure value range in the above content.

[0251] Referring to Figure 17, the drying method includes the following steps S1001 to S1003:

[0252] Step S1001: The drying equipment dries the electrode sheet according to the initial drying parameters.

[0253] In this embodiment of the present disclosure, the drying equipment 1 dries the electrode sheet according to the initial drying parameters.

[0254] In this embodiment of the disclosure, the initial drying parameters can be preset by the drying equipment or can be the drying parameters used by the drying equipment when drying other electrodes last time; the specific initial drying parameters can be set according to the actual situation, and this embodiment of the disclosure does not make specific limitations here.

[0255] In this embodiment of the present disclosure, the drying parameters include at least a first parameter for controlling the negative pressure, a second parameter for controlling the wind speed, and a third parameter for controlling the NMP concentration value in the drying equipment 1; the specific drying parameters can be determined according to the actual situation, and this embodiment of the present disclosure does not make specific limitations.

[0256] Step S1002: When the drying process for the electrode begins, the control device acquires the drying data of the electrode during the drying process at preset time intervals.

[0257] In this embodiment of the present disclosure, when the drying process for the electrode begins, the control device 2 acquires the drying data of the electrode during the drying process at preset time intervals.

[0258] In this embodiment of the disclosure, the drying data typically includes the NMP concentration value, negative pressure value, wind speed value, and appearance data of the electrode in the drying equipment 1 during the drying process; the specific drying data can be determined according to the actual situation, and this embodiment of the disclosure does not make specific limitations.

[0259] For example, the control device 2 can acquire drying data of the electrode sheet during the drying process every second or every minute, and use the drying data to adjust the initial drying parameters until the drying process is completed.

[0260] Step S1003: If the drying data does not meet the preset data reference standard, the control equipment adjusts the initial drying parameters until the drying process is completed.

[0261] In this embodiment of the present disclosure, after the control device 2 obtains the drying data, it judges the drying data. If the drying data does not meet the preset data reference benchmark, it adjusts the initial drying parameters until the drying process is completed.

[0262] In this embodiment of the present disclosure, a corresponding preset data reference benchmark can be set in advance for different drying data. When the drying data obtained by the control device 2 does not match the corresponding preset data reference benchmark, the initial drying parameters of the current drying device 1 are adjusted. That is, the initial drying parameters can be adjusted once every preset time according to the obtained drying data. A stable final drying parameter is obtained through continuous adjustment, and then the drying process can be performed on the same electrode using the final drying parameter.

[0263] It is understood that this disclosure allows for manual and automatic switching when adjusting drying parameters. Upon first startup, initial drying parameters are input as base values, and then the system switches to automatic closed-loop control, which automatically adjusts the initial drying parameters based on drying data.

[0264] In some embodiments of this disclosure, the drying data includes at least the current negative pressure value, the current wind speed value, and the current NMP concentration value; the drying parameters include at least a first parameter for controlling the negative pressure, a second parameter for controlling the wind speed, and a third parameter for controlling the NMP concentration value; when the drying data does not conform to the preset data reference benchmark, the control device 2 adjusts the initial drying parameters, referring to Figure 18, the specific method includes the following steps S1101 to S1103:

[0265] Step S1101: When the current negative pressure value is not within the preset negative pressure value range, the control device adjusts the first parameter to make the current negative pressure value within the preset negative pressure value range.

[0266] In this embodiment of the present disclosure, when the current negative pressure value is not within the preset negative pressure value range, the control device 2 adjusts the first parameter so that the current negative pressure value is within the preset negative pressure value range.

[0267] In this embodiment of the present disclosure, referring to Figures 3, 4 and 9, the drying equipment 1 includes at least two drying devices 3, each drying device 3 includes at least two ovens 31 and an exhaust manifold 34. The exhaust manifold 34 is equipped with a total pressure detection device 344. Each oven 31 includes a housing 311, and the housing 311 is equipped with a pressure detection device 326 for detecting the air pressure inside the housing 311. Thus, the current negative pressure value includes at least the overall negative pressure value corresponding to one drying device 3 in the drying equipment 1, i.e., the first negative pressure value obtained from the total pressure detection device 344, and the individual negative pressure value corresponding to the housing 311 of each oven 31, i.e., the second negative pressure value obtained from the pressure detection device 326. When the first negative pressure value corresponding to the drying device 3 and the second negative pressure value corresponding to the housing 311 of each oven 31 are not within the preset negative pressure value range, the control device 2 adjusts the first parameter for controlling the negative pressure in the drying equipment 1 to adjust the first negative pressure value and the second negative pressure value to within the preset negative pressure value range.

[0268] Step S1102: When the current wind speed value is not within the preset wind speed value range, the control device adjusts the second parameter to make the current wind speed value within the preset wind speed value range.

[0269] In this embodiment of the disclosure, when the current wind speed value is not within the preset wind speed value range, the control device 2 adjusts the second parameter so that the current wind speed value is within the preset wind speed value range.

[0270] In this embodiment of the present disclosure, referring to Figures 3, 4 and 9, the drying equipment 1 includes at least two drying devices 3, and each drying device 3 includes at least two ovens 31. Each oven 31 includes a box body 311 and a first air box 312 disposed within the box body 311. The first air box 312 has a first box wall 3121. The outer side of the first box wall 3121 is provided with a drying area 20 for the electrode 100 to pass through. An air box inlet speed measuring device 370 is provided inside the oven 31. Thus, the current wind speed value is obtained from the air box inlet speed measuring device 370 of each oven 31, which is the wind speed value of the gas after the convergence of the circulating air and fresh air. That is, when the current wind speed value measured by the air box inlet speed measuring device 370 of each oven 31 in the drying equipment 3 is not within the preset wind speed value range, the control device 2 adjusts the second parameter for controlling the wind speed in the drying equipment 1 to adjust the current wind speed value to within the preset wind speed value range.

[0271] Step S1103: When the current NMP concentration value is not within the preset NMP concentration value range, the control device adjusts the third parameter to make the current NMP concentration value within the preset NMP concentration value range.

[0272] In this embodiment of the disclosure, when the current NMP concentration value is not within the preset NMP concentration value range, the control device 2 adjusts the third parameter to make the current NMP concentration value within the preset NMP concentration value range.

[0273] In this embodiment of the disclosure, the preset negative pressure range, preset wind speed range, and preset NMP concentration range are preset for the drying equipment.

[0274] For example, referring to Figure 19, an exemplary drying process is given to illustrate steps S1101 to S1103, specifically including steps S1201 to S1204:

[0275] Step S1201: Set the initial drying parameters before turning on the heating of the drying equipment. After setting them, start the heating of the drying equipment to prepare for coating.

[0276] In this embodiment of the disclosure, the initial drying parameters include at least the first fresh air frequency of the main fresh air fan, the first exhaust air frequency of the main exhaust fan, the opening degree of the first fresh air valve of the main fresh air fan, the opening degree of the first exhaust air valve of the main exhaust fan, the initial NMP concentration setting value of each drying oven, the second fresh air frequency of the fresh air fan of each drying oven, the first opening degree of the fresh air valve, the second exhaust air frequency of the exhaust fan, the second opening degree of the exhaust air valve, the heating temperature of the heat exchange device, and the output power of the frequency converter in the circulating fan, etc. The specific initial drying parameters can be determined according to the actual situation, and this embodiment of the disclosure does not make specific limitations here.

[0277] Step S1202: If the current negative pressure value is not within the preset negative pressure value range, adjust the opening of the first exhaust air valve of the main exhaust fan and / or the opening of the first fresh air valve of the main fresh air fan to adjust the current negative pressure value to within the preset negative pressure value range.

[0278] In this embodiment of the present disclosure, the current negative pressure value includes at least a first negative pressure value corresponding to one drying device in the drying equipment 1 and a second negative pressure value corresponding to the chamber of each drying oven in the drying equipment. Therefore, the control device 2 obtains the first negative pressure value from the total pressure detection device of the drying equipment 1 every preset time period. If the first negative pressure value is not within the first preset negative pressure value range, the opening degree of the first exhaust valve of the main exhaust fan and / or the opening degree of the first fresh air valve of the main fresh air fan can be adjusted to bring the first negative pressure value within the first preset negative pressure value range. Then, the control device 2 obtains the second negative pressure value corresponding to the box body of each oven from the air pressure detection device of each oven in the drying device. If the second negative pressure value is not within the second preset negative pressure value range, the second fresh air frequency of the fresh air fan, the first opening degree of the fresh air valve, the second exhaust frequency of the exhaust fan, and the second opening degree of the exhaust valve of each oven section can be selectively adjusted to adjust the second negative pressure value to within the second preset negative pressure value range. The specific adjustment method can be determined according to the actual situation, and this embodiment does not make specific limitations here.

[0279] Step S1203: If the current wind speed value is not within the preset wind speed value range, adjust the output power of the frequency converter in the circulating fan to adjust the current wind speed value to within the preset wind speed value range.

[0280] In this embodiment of the present disclosure, after adjusting the current negative pressure value to within the preset negative pressure value range, the control device 2 obtains the current wind speed value of the circulating air and the gas after the fresh air convergence in each oven of the drying device 1 from the air inlet speed measuring device. If the current wind speed value is not within the preset wind speed value range, the output power of the frequency converter in the circulating fan can be adjusted to adjust the current wind speed value to within the preset wind speed value range. The specific adjustment method can be determined according to the actual situation, and this embodiment of the present disclosure does not make specific limitations here.

[0281] Step S1204: If the current NMP concentration value is not within the preset NMP concentration value range, adjust the opening degree of the first fresh air valve and / or the first fresh air frequency of the main fresh air fan to adjust the current NMP concentration value to within the preset NMP concentration value range.

[0282] In this embodiment of the present disclosure, the current NMP concentration value includes at least a first NMP concentration value obtained from the total exhaust NMP concentration measuring device of the drying unit of the drying equipment 1, and a second NMP concentration value obtained from the NMP concentration measuring device of each oven in the drying equipment. Therefore, after adjusting the current wind speed value to a preset wind speed range, the control device 2 first obtains the first NMP concentration value from the total exhaust NMP concentration measuring device of the drying unit of the drying equipment 1. If the first NMP concentration value is not within the first preset NMP concentration value range, the opening degree of the first fresh air valve and / or the first fresh air frequency of the main fresh air fan can be adjusted to reduce the NMP concentration. The concentration value is adjusted to within the first preset NMP concentration value range. Then, the second NMP concentration value is obtained from the NMP concentration measuring device of each oven in the drying device. If the second NMP concentration value is not within the second preset NMP concentration value range, the second fresh air frequency of the fresh air fan, the first opening degree of the fresh air valve, the second exhaust frequency of the exhaust fan, and the second opening degree of the exhaust valve of each oven section can be selectively adjusted, or the heating temperature of the heat exchange device can be adjusted to adjust the second NMP concentration value to within the second preset NMP concentration value range. The specific adjustment method can be determined according to the actual situation, and this embodiment does not make specific limitations here.

[0283] In this embodiment of the present disclosure, referring to Figures 2, 3, and 4, the drying equipment 1 includes at least two drying devices 3, each drying device 3 including at least two drying ovens 31 and an exhaust manifold 34. In the same drying device 3, the exhaust ports 3112 of all drying ovens 31 are connected to the exhaust manifold 34 via pipes. The exhaust manifold 34 is equipped with a total exhaust NMP concentration measuring device 343. Meanwhile, each drying oven 31 includes a housing 311, and the housing 311 is equipped with an exhaust port 3112 connected to a return air channel for discharging some of the gas in the return air channel. The housing 311 is equipped with an NMP concentration measuring device 325 at the exhaust port 3112. Therefore, the current NMP concentration value includes at least the drying... The overall NMP concentration value corresponding to a drying device 3 in equipment 1, namely the first NMP concentration value obtained from the total exhaust NMP concentration measuring device 343, and the individual NMP concentration value discharged from the chamber 311 of each oven 31, namely the second NMP concentration value obtained from the NMP concentration measuring device 325, are used to adjust the third parameter controlling the NMP concentration value in the drying equipment 1 when the first NMP concentration value corresponding to the drying device 3 and the second NMP concentration value corresponding to the chamber 311 of each oven 31 are not within the preset NMP concentration value range, so as to adjust the first NMP concentration value and the second NMP concentration value to within the preset NMP concentration value range.

[0284] Based on the above embodiments, in some embodiments of this disclosure, referring to Figures 3 and 4, the drying equipment 1 includes an oven 31 and an exhaust manifold 34. The exhaust manifold 34 is equipped with a total pressure detection device 344. The oven 31 includes a box body 311. The inner wall of the box body 311 is equipped with a pressure detection device 326. The current negative pressure value includes at least a first negative pressure value obtained from the total pressure detection device 344 and a second negative pressure value obtained from the pressure detection device 326. When the current negative pressure value is not within the preset negative pressure value range, the control device 2 adjusts the first parameter. Referring to Figure 20, the specific method includes the following steps S1301 to S1303:

[0285] Step S1301: When the first negative pressure value is not within the first preset negative pressure value range, the control device adjusts the first sub-parameter.

[0286] In this embodiment of the present disclosure, when the first negative pressure value is not within the first preset negative pressure value range, the control device 2 adjusts the first sub-parameter.

[0287] In this embodiment of the disclosure, since the current negative pressure value includes at least the first negative pressure value obtained from the total pressure detection device 344 and the second negative pressure value obtained from the air pressure detection device 326, the control device 2 needs to adjust the first sub-parameter affecting the first negative pressure value in the drying device 1 when the first negative pressure value corresponding to a drying device 3 in the drying device 1 is not in the first preset negative pressure value range, so as to adjust the first negative pressure value to the first preset negative pressure value range, and then judge the second negative pressure value.

[0288] Step S1302: After the control device adjusts the first sub-parameter and the first negative pressure value is within the first preset negative pressure value range, it obtains the second negative pressure value.

[0289] In this embodiment of the disclosure, after the control device 2 adjusts the first sub-parameter and the first negative pressure value is within the first preset negative pressure value range, it obtains the second negative pressure value.

[0290] In this embodiment of the present disclosure, after the control device 2 adjusts the first sub-parameter affecting the first negative pressure value in the drying device 1 to adjust the first negative pressure value to within the first preset negative pressure value range, it needs to obtain the second negative pressure value corresponding to the box 311 of each oven 31 from the air pressure detection device 326 and judge the second negative pressure value.

[0291] Step S1303: When the second negative pressure value is not within the second preset negative pressure value range, the control device adjusts the second sub-parameter.

[0292] In this embodiment of the present disclosure, the control device 2 adjusts the second sub-parameter when the second negative pressure value is not within the second preset negative pressure value range.

[0293] In this embodiment of the present disclosure, after the control device 2 obtains the second negative pressure value corresponding to the box 311 of each oven 31 from the air pressure detection device 326, if it determines that the second negative pressure value is not within the second preset negative pressure value range, it adjusts the second sub-parameter of the drying device 1 that affects the second negative pressure value so as to adjust the second negative pressure value to within the second preset negative pressure value range.

[0294] In this embodiment, since the drying equipment 1 includes at least two drying devices 3, and each drying device 3 includes at least two ovens 31, and the first negative pressure value is the overall negative pressure value corresponding to one drying device 3 in the drying equipment 1, and the second negative pressure value is the individual negative pressure value corresponding to the box body 311 of each oven 31 in the drying device 3, when setting the first preset negative pressure value range corresponding to the first negative pressure value of each drying device 3, a corresponding first preset negative pressure value range can be set for different drying devices 3. When setting the second preset negative pressure value range corresponding to the second negative pressure value of the box body 311 of each oven 31, a corresponding second preset negative pressure value range can be set for different ovens 31. When judging the current negative pressure value, this disclosure can first judge the first negative pressure value for different drying devices 3, and then judge the second negative pressure value for each oven in each drying device 3. The specific judgment process can be selected according to the actual situation, and this embodiment does not make specific limitations here.

[0295] In some embodiments of this disclosure, referring to FIG3, the drying device 3 further includes a fresh air main duct 33, which is equipped with a main fresh air fan 331, and the exhaust main duct 34 is also equipped with a main exhaust fan 341; the control device 2 adjusts the first sub-parameter, referring to FIG21, and the specific method includes the following steps S1401:

[0296] Step S1401: The control device performs PID control algorithm calculation based on the first negative pressure value and the first preset negative pressure value range to obtain the first analog quantity, and adjusts the first fresh air frequency of the main fresh air fan and / or the first exhaust air frequency of the main exhaust fan based on the first analog quantity.

[0297] In this embodiment of the disclosure, the control device 2 performs PID control algorithm calculation based on the first negative pressure value and the first preset negative pressure value range to obtain a first analog quantity, and adjusts the first fresh air frequency of the main fresh air fan 331 and / or the first exhaust air frequency of the main exhaust fan 341 based on the first analog quantity.

[0298] In this embodiment, the first sub-parameter includes at least the first fresh air frequency of the main fresh air fan 331 and the first exhaust air frequency of the main exhaust fan 341. Therefore, when the first negative pressure value corresponding to a drying device 3 in the drying equipment 1 is not within the first preset negative pressure value range, the control device 2 can adjust the first fresh air frequency of the main fresh air fan 331, the first exhaust air frequency of the main exhaust fan, or simultaneously adjust both the first fresh air frequency of the main fresh air fan 331 and the first exhaust air frequency of the main exhaust fan, as long as the exhaust air velocity is slightly larger than the inlet air velocity. The specific adjustment method can be selected according to the actual situation, and this embodiment does not impose specific limitations here.

[0299] In some embodiments of this disclosure, referring to FIG4, the housing 311 is provided with a fresh air inlet 3111 and an exhaust air outlet 3112. The control device 2 adjusts the second sub-parameter, referring to FIG22, and the specific method includes the following steps S1501:

[0300] Step S1501: The control device performs PID calculation based on the second negative pressure value and the second preset negative pressure value range to obtain a second analog quantity, and adjusts the air intake volume of the fresh air inlet and / or the exhaust volume of the exhaust air outlet based on the second analog quantity.

[0301] In this embodiment of the present disclosure, the control device 2 performs PID calculation based on the second negative pressure value and the second preset negative pressure value range to obtain a second analog quantity, and adjusts the air intake volume of the fresh air inlet 3111 and / or the exhaust volume of the exhaust outlet 3112 based on the second analog quantity.

[0302] In this embodiment of the present disclosure, the second sub-parameter includes at least the air intake volume of the fresh air inlet 3111 and the exhaust volume of the exhaust outlet 3112. Therefore, when the second negative pressure value corresponding to the chamber 311 of the oven 31 is not within the second preset negative pressure value range, the control device 2 can adjust the air intake volume of the fresh air inlet, the exhaust volume of the exhaust outlet, or both the air intake volume of the fresh air inlet and the exhaust volume of the exhaust outlet simultaneously, as long as the exhaust air velocity is slightly greater than the intake air velocity to maintain the negative pressure. The specific adjustment method can be selected according to the actual situation, and this embodiment of the present disclosure does not make specific limitations here.

[0303] For example, referring to Figures 23, 24, and 25, an exemplary adjustment process for the first parameter is given to illustrate steps S1301 to S1501, specifically including steps S1601 to S1807:

[0304] Assume that the first preset negative pressure value range corresponding to the drying device 3 is [-35pa, -15pa], and at the same time, assume that the drying device 3 includes 12 drying ovens 31, the second preset negative pressure value range corresponding to the box body 311 of each drying oven 31 is [-45pa, -5pa], and the first drying oven 31 and the last drying oven 31 are set with a third preset negative pressure value range of [-25pa, -5pa].

[0305] Step S1601: Obtain the first negative pressure value from the total pressure detection device.

[0306] Step S1602: Determine whether the first negative pressure value is less than -35pa.

[0307] Specifically, if the first negative pressure value is less than -35 Pa, proceed to step S1603; if the first negative pressure value is not less than -35 Pa, proceed to step S1604.

[0308] Step S1603: Reduce the first exhaust frequency of the main exhaust fan.

[0309] Step S1604: Determine whether the first negative pressure value is greater than -15 Pa.

[0310] Specifically, if the first negative pressure value is greater than -15 Pa, proceed to step S1605; if the first negative pressure value is not greater than -15 Pa, proceed to step S1607.

[0311] Step S1605: Increase the first exhaust frequency of the main exhaust fan.

[0312] Step S1606: Obtain the first negative pressure value from the total pressure detection device again, and determine whether the first negative pressure value is greater than -35pa and less than -15pa.

[0313] Specifically, if the first negative pressure value is -25 Pa, that is, greater than -35 Pa and less than -15 Pa, then proceed to step S1607; if the first negative pressure value does not meet the condition of being greater than -35 Pa and less than -15 Pa, then proceed to step S1602 again.

[0314] Step S1607: The first negative pressure value adjustment closed loop ends.

[0315] Specifically, after the first negative pressure value adjustment closed loop ends, the second negative pressure value adjustment closed loop begins, proceeding to step S1701.

[0316] Step S1701: For each oven section, obtain the second negative pressure value corresponding to the oven body from the air pressure detection device of each oven section.

[0317] Step S1702: Determine whether the second negative pressure value is less than -45 Pa.

[0318] Specifically, if the second negative pressure value is less than -45 Pa, proceed to step S1703; if the second negative pressure value is not less than -45 Pa, proceed to step S1704.

[0319] Step S1703: Reduce the second exhaust frequency of the exhaust fan of this section of the oven.

[0320] Step S1704: Determine whether the second negative pressure value is greater than -5pa.

[0321] Specifically, if the second negative pressure value is greater than -5 Pa, proceed to step S1705; if the second negative pressure value is not greater than -5 Pa, proceed to step S1707.

[0322] Step S1705: Increase the second exhaust frequency of the exhaust fan in this section of the oven.

[0323] Step S1706: Obtain the second negative pressure value again from the air pressure detection device of the oven section, and determine whether the second negative pressure value is greater than -45pa and less than -5pa.

[0324] Specifically, if the second negative pressure value is -25 Pa, that is, greater than -45 Pa and less than -5 Pa, then proceed to step S1707; if the second negative pressure value does not meet the requirement of being greater than -45 Pa and less than -5 Pa, then proceed to step S1702 again.

[0325] Step S1707: The second negative pressure value adjustment closed loop ends.

[0326] Specifically, the second negative pressure value adjustment closed loop ends, and the third negative pressure value adjustment closed loop begins, proceeding to step S1801.

[0327] Step S1801: Obtain the third negative pressure value again from the first section of the oven / the last section of the oven.

[0328] Step S1802: Determine whether the third negative pressure value is less than -25 Pa.

[0329] Specifically, if the third negative pressure value is less than -25 Pa, proceed to step S1803; if the third negative pressure value is not less than -25 Pa, proceed to step S1804.

[0330] Step S1803: Reduce the second exhaust frequency of the exhaust fan of the first section / last section of the drying oven.

[0331] Step S1804: Determine whether the third negative pressure value is greater than -5pa.

[0332] Specifically, if the third negative pressure value is greater than -5 Pa, proceed to step S1805; if the third negative pressure value is not greater than -5 Pa, proceed to step S1807.

[0333] Step S1805: Increase the second exhaust frequency of the exhaust fan of the first / last oven section.

[0334] Step S1806: Obtain the third negative pressure value again from the air pressure detection device of the first oven / last oven, and determine whether the third negative pressure value is greater than -25pa and less than -5pa.

[0335] Specifically, if the third negative pressure value is -15 Pa, that is, greater than -25 Pa and less than -5 Pa, then proceed to step S1807; if the third negative pressure value does not meet the requirement of being greater than -25 Pa and less than -5 Pa, then proceed to step S1802 again.

[0336] Step S1807: Negative pressure regulation closed loop ends.

[0337] In some embodiments of this disclosure, referring to Figures 4 and 6, the oven 31 further includes a first air box 312 and a circulating fan 318 disposed within the chamber 311. An air box inlet speed measuring device 370 is provided inside the oven 31, and the current wind speed value is obtained from the air box inlet speed measuring device 370. The control device 2 adjusts the second parameter, referring to Figure 26, specifically including the following steps S1901:

[0338] Step S1901: Control equipment adjusts the output power of the frequency converter in the circulating fan.

[0339] In this embodiment of the disclosure, the control device 2 adjusts the output power of the frequency converter in the circulating fan 318.

[0340] In this embodiment of the present disclosure, the second parameter includes at least the output power of the inverter in the circulating fan 318. Therefore, when the current wind speed value of the gas blown toward the electrode in the first air box 312 of each oven 31 in the drying device 3 is not within the preset wind speed value range, the control device 2 adjusts the output power of the inverter in the circulating fan 318 to adjust the current wind speed value to within the preset wind speed value range.

[0341] Referring to Figure 27, an exemplary adjustment process for the second parameter is given to illustrate step S1901, specifically including steps S2001 to S2006:

[0342] Step S2001: Set the preset wind speed range for each oven section.

[0343] Step S2002: Obtain the current wind speed value of the oven section from the air inlet speed measuring device of the oven section.

[0344] Step S2003: Determine whether the current wind speed value is within the preset wind speed value range.

[0345] Specifically, if the preset wind speed value of the oven is set to V1 and the current wind speed value is V2, determine whether the absolute value of V1-V2 is greater than 0.1. If it is greater, it indicates that the current wind speed value is not within the preset wind speed value range, and proceed to step S2004. If it is not greater, it indicates that the current wind speed value is within the preset wind speed value range, and proceed to step S2006.

[0346] Step S2004: Adjust the output power of the frequency converter in the circulating fan.

[0347] Specifically, closed-loop control (Proportion Integral Differential, PID) calculations are performed to adjust the output power of the frequency converter in the circulating fan in order to regulate the current wind speed value.

[0348] Step S2005: Obtain the current wind speed value again from the air inlet speed measuring device of the oven in this section, and determine whether the current wind speed value is within the preset wind speed value range.

[0349] Specifically, if the current wind speed value is not within the preset wind speed value range, then proceed to step S2004 again; if the current wind speed value is within the preset wind speed value range, then proceed to step S2006.

[0350] Step S2006: Maintain the output power of the frequency converter in the circulating fan, and the closed loop of wind speed regulation ends.

[0351] In some embodiments of this disclosure, referring to Figures 2, 3, and 4, the main exhaust pipe 34 of the drying device 3 in the drying equipment 1 is equipped with a main exhaust NMP concentration measuring device 343, and the box 311 of the drying oven 31 in the drying device 3 is equipped with an exhaust port 3112. An NMP concentration measuring device 325 is installed at the exhaust port 3112. The current NMP concentration value includes at least a first NMP concentration value obtained from the main exhaust NMP concentration measuring device 343 and a second NMP concentration value obtained from the NMP concentration measuring device 325. When the current NMP concentration value is not within the preset NMP concentration value range, the control device 2 adjusts a third parameter. Referring to Figure 28, the specific method includes the following steps S2101 to S2103:

[0352] Step S2101: When the first NMP concentration value is not within the first preset NMP concentration value range, the control device adjusts the third sub-parameter.

[0353] In this embodiment of the disclosure, the control device 2 adjusts the third sub-parameter when the first NMP concentration value is not within the first preset NMP concentration value range.

[0354] In this embodiment of the disclosure, since the current negative pressure value includes at least the first NMP concentration value obtained from the main exhaust NMP concentration measuring device 343 and the second NMP concentration value obtained from the NMP concentration measuring device 325, the control device 2 needs to adjust the third sub-parameter affecting the first NMP concentration value in the drying device 1 when the first NMP concentration value corresponding to a drying device 3 in the drying device 1 is not in the first preset NMP concentration value range, so as to adjust the first NMP concentration value to be within the first preset NMP concentration value range, and then judge the second NMP concentration value.

[0355] Step S2102: After the control device adjusts the third sub-parameter and the first NMP concentration value is within the first preset NMP concentration value range, it obtains the second NMP concentration value.

[0356] In this embodiment of the disclosure, after the control device 2 adjusts the third sub-parameter and the first NMP concentration value is within the first preset NMP concentration value range, it obtains the second NMP concentration value.

[0357] In this embodiment of the present disclosure, after the control device 2 adjusts the third sub-parameter affecting the first NMP concentration value in the drying device 1 to adjust the first NMP concentration value to within the first preset NMP concentration value range, it needs to obtain the second NMP concentration value corresponding to the chamber 311 of each oven 31 from the NMP concentration measuring device 325 and judge the second NMP concentration value.

[0358] Step S2103: When the second NMP concentration value is not within the second preset NMP concentration value range, the control device adjusts the fourth sub-parameter.

[0359] In this embodiment of the disclosure, when the second NMP concentration value is not within the second preset NMP concentration value range, the control device 2 adjusts the fourth sub-parameter.

[0360] In this embodiment of the present disclosure, after the control device 2 obtains the second NMP concentration value corresponding to the chamber 311 of each oven 31 in the NMP concentration measuring device 325, if it is determined that the second NMP concentration value is not within the second preset NMP concentration value range, the fourth sub-parameter affecting the second NMP concentration value in the drying device 1 is adjusted so as to adjust the second NMP concentration value to within the second preset NMP concentration value range.

[0361] In this embodiment of the present disclosure, since the drying equipment 1 includes at least two drying devices 3, and each drying device 3 includes at least two ovens 31, and the first NMP concentration value is the overall discharge NMP concentration value corresponding to one drying device 3 in the drying equipment 1, and the second NMP concentration value is the individual NMP concentration value corresponding to the chamber 311 of each oven 31 in the drying device 3, when setting the first preset NMP concentration value range corresponding to the first NMP concentration value of each drying device 3, the corresponding first preset NMP concentration value range can be set for different drying devices 3. When setting the second preset NMP concentration value range corresponding to the second NMP concentration value of the chamber 311 of each oven 31, the corresponding second preset NMP concentration value range can be set for different ovens 31. When judging the current NMP concentration value, the present disclosure can first judge the first NMP concentration value for different drying devices 3, and then judge the second NMP concentration value for each oven in each drying device 3. The specific judgment process can be selected according to the actual situation, and the present disclosure embodiment does not make specific limitations here.

[0362] In some embodiments of this disclosure, referring to Figures 4 and 6, the housing 311 is provided with a first air box 312, a circulating fan 318, and a heat exchange device 350. The heat exchange device 350 is used to heat the temperature of the gas after the circulating air and fresh air converge. The control device 2 adjusts the third sub-parameter. Referring to Figure 29, the specific method includes the following steps S2201:

[0363] Step S2201: Control the equipment to adjust the output power of the frequency converter in the circulating fan and / or adjust the heating temperature of the heat exchange device.

[0364] In this embodiment of the disclosure, the control device 2 adjusts the output power of the frequency converter in the circulating fan 318 and / or adjusts the heating temperature of the heat exchange device 350.

[0365] In this embodiment, the third sub-parameter includes at least the output power of the inverter in the circulating fan 318 and the heating temperature of the heat exchange device 350. Therefore, when the first NMP concentration value corresponding to a drying device 3 in the drying equipment 1 is not within the first preset NMP concentration value range, the control device 2 can adjust the output power of the inverter in the circulating fan 318, adjust the heating temperature of the heat exchange device 350, or simultaneously adjust both the output power of the inverter in the circulating fan 318 and the heating temperature of the heat exchange device 350. The specific adjustment method can be selected according to the actual situation, and this embodiment does not impose specific limitations here.

[0366] In some embodiments of this disclosure, referring to FIG4, the housing 311 is further provided with a fresh air inlet 3111; the control device 2 adjusts the fourth sub-parameter, referring to FIG30, and the specific method includes the following steps S2301:

[0367] Step S2301: The control device performs PID calculations based on the second NMP concentration value and the second preset NMP concentration value range to obtain a third analog quantity, and adjusts the air intake volume of the fresh air inlet and / or the exhaust volume of the exhaust air outlet based on the third analog quantity; and / or, the control device adjusts the heating temperature of the heat exchange device.

[0368] In this embodiment of the disclosure, the control device 2 performs PID calculations based on the second NMP concentration value and the second preset NMP concentration value range to obtain a third analog quantity, and adjusts the air intake volume of the fresh air inlet 3111 and / or the exhaust volume of the exhaust outlet 3112 based on the third analog quantity; and / or, the control device 2 adjusts the heating temperature of the heat exchange device 350.

[0369] In this embodiment, the fourth sub-parameter includes at least the air intake volume of the fresh air inlet 3111, the exhaust volume of the exhaust outlet 3112, and the heating temperature of the heat exchange device 350. Therefore, when the second NMP concentration value corresponding to the chamber 311 of the oven 31 is not within the second preset NMP concentration value range, the control device 2 can adjust the air intake volume of the fresh air inlet, or simultaneously adjust the air intake volume of the fresh air inlet 3111 and the exhaust volume of the exhaust outlet 3112 according to a preset ratio, or adjust the heating temperature of the heat exchange device 350, or simultaneously adjust the air intake volume of the fresh air inlet and the heating temperature of the heat exchange device 350, or simultaneously adjust the air intake volume of the fresh air inlet 3111 and the exhaust volume of the exhaust outlet 3112 according to a preset ratio. The specific adjustment method can be selected according to the actual situation, and this embodiment does not impose specific limitations here.

[0370] In some embodiments of this disclosure, referring to Figures 3 and 4, a fresh air fan 319 and a fresh air valve 320 are provided at the fresh air inlet 3111; the control device 2 adjusts the air intake volume of the fresh air inlet 3111, referring to Figure 31, the specific method includes the following steps S2401:

[0371] Step S2401: The control equipment adjusts the second fresh air frequency of the fresh air fan and / or adjusts the first opening degree of the fresh air valve.

[0372] In this embodiment of the disclosure, the control device 2 adjusts the second fresh air frequency of the fresh air fan 319 and / or adjusts the first opening degree of the fresh air valve 320.

[0373] In this embodiment of the present disclosure, when the control device 2 adjusts the air intake volume of the fresh air inlet 3111, it can adjust the second fresh air frequency of the fresh air fan 319 to achieve the purpose of adjusting the air intake volume of the fresh air inlet 3111, or it can adjust the first opening degree of the fresh air valve 320 to achieve the purpose of adjusting the air intake volume of the fresh air inlet 3111, or it can simultaneously adjust the second fresh air frequency of the fresh air fan 319 and the first opening degree of the fresh air valve 320 to achieve the purpose of adjusting the air intake volume of the fresh air inlet 3111; the specific adjustment method can be selected according to the actual situation, and this embodiment of the present disclosure does not make specific limitations.

[0374] In some embodiments of this disclosure, referring to Figures 3 and 4, an exhaust fan 322 and an exhaust valve 323 are provided at the exhaust port 3112; the control device 2 adjusts the exhaust volume of the exhaust port 3112, referring to Figure 32, the specific method includes the following steps S2501:

[0375] Step S2501: Control the equipment to adjust the second exhaust frequency of the exhaust fan and / or adjust the second opening of the exhaust valve.

[0376] In this embodiment of the disclosure, the control device 2 adjusts the second exhaust frequency of the exhaust fan 322 and / or adjusts the second opening degree of the exhaust valve 323.

[0377] In this embodiment of the present disclosure, when the control device 2 adjusts the exhaust volume of the exhaust vent 3112, it can adjust the second exhaust frequency of the exhaust fan 322 to achieve the purpose of adjusting the exhaust volume of the exhaust vent 3112, or it can adjust the second opening degree of the exhaust valve 323 to achieve the purpose of adjusting the exhaust volume of the exhaust vent 3112, or it can simultaneously adjust the second exhaust frequency of the exhaust fan 322 and the second opening degree of the exhaust valve 323 to achieve the purpose of adjusting the exhaust volume of the exhaust vent 3112; the specific adjustment method can be selected according to the actual situation, and this embodiment of the present disclosure does not make specific limitations.

[0378] Referring to Figure 33, an exemplary procedure for adjusting the fourth sub-parameter based on the second NMP concentration value is provided to illustrate step S2103, specifically including steps S2601 to S2606:

[0379] Step S2601: Set the second preset NMP concentration value range for each oven section.

[0380] Step S2602: Obtain the second NMP concentration value of the current oven from the NMP concentration measuring device of the current oven.

[0381] Step S2603: Determine whether the second NMP concentration value is within the second preset NMP concentration value range.

[0382] Step S2604: Adjust the air intake of the fresh air inlet and the air exhaust of the exhaust outlet.

[0383] Specifically, PID calculations are performed to obtain analog values, and the air intake and exhaust volumes of the fresh air inlet and exhaust outlet of the oven 31 are adjusted based on these analog values ​​to regulate the second NMP concentration value of the oven 31.

[0384] Step S2605: Obtain the second NMP concentration value of the current oven from the NMP concentration measuring device of the current oven again, and determine whether the second NMP concentration value is within the second preset NMP concentration value range.

[0385] Specifically, if the second NMP concentration value is not within the second preset NMP concentration value range, then proceed to step S2604 again; if the second NMP concentration value is within the second preset NMP concentration value range, then proceed to step S2606.

[0386] Step S2606: Maintain the air intake volume at the fresh air inlet and the exhaust volume at the exhaust outlet of the oven in this section. The NMP concentration adjustment closed loop ends.

[0387] For example, referring to Figures 34 and 35, an exemplary adjustment process for the third parameter is given to illustrate steps S2101 to S2501, specifically including steps S2701 to S2809:

[0388] Assume that the drying equipment 1 includes a first drying device 3 and a second drying device 3. Both the first drying device 3 and the second drying device 3 include 12 drying ovens. The first preset NMP concentration value range for each drying device 3 is [LEL 30%, LEL 35%], where LEL (lower explosion limit) is relative to NMP. At the same time, the second preset NMP concentration value range for the second to tenth drying ovens 31 of each drying device 3 is [LEL 20%, LEL 40%], and the third preset NMP concentration value range for the last drying oven 31 of each drying device 3 is [LEL 0%, LEL 5%].

[0389] Step S2701: Obtain the first NMP concentration value from the NMP concentration measuring device in the main exhaust air.

[0390] Step S2702: Determine whether the first NMP concentration value is greater than or equal to LEL40%.

[0391] Specifically, if the first NMP concentration value is greater than or equal to LEL40%, proceed to step S2703; if the first NMP concentration value is less than LEL40%, proceed to step S2705.

[0392] Step S2703: Reduce the output power of the frequency converter in the circulating fan and / or lower the heating temperature of the heat exchange device.

[0393] Step S2704: Obtain the first NMP concentration value from the main exhaust NMP concentration measuring device again, and determine whether the first NMP concentration value is less than LEL40%.

[0394] Specifically, if the first NMP concentration value is less than LEL40%, proceed to step S2705; if the first NMP concentration value is not less than LEL40%, proceed back to step S2703.

[0395] Step S2705: Obtain the second NMP concentration value corresponding to each oven section from the NMP concentration measuring device of each oven section.

[0396] Step S2706: Determine whether there is an oven with a second NMP concentration value less than LEL20%.

[0397] Specifically, if there is an oven with a second NMP concentration value less than LEL20%, proceed to step S2707; if there is no oven with a second NMP concentration value less than LEL20%, proceed to step S2709.

[0398] Step S2707: Increase the second fresh air frequency of the fresh air fan of the oven section and / or increase the heating temperature of the heat exchange device.

[0399] Step S2708: Obtain the second NMP concentration value again from the NMP concentration measuring device of the oven section, and determine whether the second NMP concentration value is greater than or equal to LEL20%.

[0400] Specifically, if the second NMP concentration value obtained again is greater than or equal to LEL20%, then proceed to step S2709; if the second NMP concentration value obtained again is less than LEL20%, then proceed to step S2707 again.

[0401] Step S2709: The first stage of NMP concentration adjustment closed loop ends.

[0402] Specifically, after the first stage of NMP concentration adjustment closed loop ends, the second stage of NMP concentration adjustment begins, proceeding to step S2801.

[0403] Step S2801: Obtain the first NMP concentration value again from the NMP concentration measuring device in the main exhaust air.

[0404] Step S2802: Determine whether the first NMP concentration value is greater than LEL35%.

[0405] Specifically, if the first NMP concentration value is greater than LEL35%, proceed to step S2803; if the first NMP concentration value is not greater than LEL35%, proceed to step S2804.

[0406] Step S2803: Increase the opening degree of the first fresh air valve of the main fresh air fan and / or the first fresh air frequency.

[0407] Step S2804: Determine whether the first NMP concentration value is less than LEL30%.

[0408] Specifically, if the first NMP concentration value is less than LEL30%, proceed to step S2805; if the first NMP concentration value is not less than LEL30%, proceed to step S2807.

[0409] Step S2805: Reduce the opening degree of the first fresh air valve of the main fresh air fan and / or the first fresh air frequency.

[0410] Step S2806: Obtain the first NMP concentration value from the main exhaust NMP concentration measuring device again, and determine whether the second NMP concentration value is greater than LEL30% and less than LEL35%.

[0411] Specifically, if the second NMP concentration value is greater than LEL30% and less than LEL35%, then proceed to step S2807; if the second NMP concentration value does not meet the condition of being greater than LEL30% and less than LEL35%, then re-proceed to step S2805.

[0412] Step S2807: Obtain the third NMP concentration value of the last oven section and determine whether the third NMP concentration value is greater than LEL5%.

[0413] Specifically, if the third NMP concentration value is greater than LEL5%, proceed to step S2808; if the third NMP concentration value is not greater than LEL5%, proceed to step S2809.

[0414] Step S2808: Increase the second fresh air frequency of the fresh air fan in the oven with the lowest second NMP concentration value from the second to the tenth ovens, and / or increase the heating temperature of the heat exchange device.

[0415] Step S2809: The second stage of NMP concentration adjustment closed loop ends.

[0416] For example, referring to Figure 36, another exemplary process for adjusting the third parameter is given, specifically including steps S2901 to S2906:

[0417] Step S2901: During the stable coating stage, obtain the first NMP concentration value of the first section of the first oven in the drying device for each side.

[0418] Step S2902: Determine whether the NMP concentration value of the first section is less than LEL10%.

[0419] Specifically, if the NMP concentration value of the first section is less than LEL10%, proceed to step S2903; if the NMP concentration value of the first section is not less than LEL10%, proceed to step S2904.

[0420] Step S2903: Increase the output power of the frequency converter in the circulating fan and / or increase the heating temperature of the heat exchange device.

[0421] Step S2904: Determine whether the overall NMP concentration value of each drying unit is less than LEL35% and greater than LEL30%.

[0422] Specifically, if the overall NMP concentration is less than LEL35% and greater than LEL30%, proceed to step S2906; if the overall NMP concentration does not meet the condition of being less than LEL35% and greater than LEL30%, proceed to step S2905.

[0423] Step S2905: Fine-tune the opening degree of the first fresh air valve and / or the first fresh air frequency of the main fresh air fan.

[0424] Step S2906: The NMP concentration value has been adjusted during the stable coating stage.

[0425] In some embodiments of this disclosure, the drying data also includes the current temperature value, and the drying parameters also include a fourth parameter for controlling the temperature. If the drying data does not conform to a preset data reference standard, the control device adjusts the initial drying parameters. Referring to Figure 37, the specific method includes the following steps S3001:

[0426] Step S3001: When the current temperature value is not within the preset temperature value range, the control device adjusts the fourth parameter to make the current temperature value within the preset temperature value range.

[0427] In this embodiment of the disclosure, when the current temperature value is not within the preset temperature value range, the control device 2 adjusts the fourth parameter to make the current temperature value within the preset temperature value range.

[0428] In this embodiment of the present disclosure, the control device 2 can adjust the fourth parameter of the temperature control in the drying device 1 to increase the current temperature value when the current temperature value is less than the preset temperature value range, or it can adjust the fourth parameter of the temperature control in the drying device 1 to decrease the current temperature value when the current temperature value is greater than the preset temperature value range.

[0429] In some embodiments of this disclosure, referring to FIG3, the return air duct is further provided with a return air temperature measuring device 330, and the current temperature value is obtained from the return air temperature measuring device 330. The heat exchange device 350 also includes a thermal oil flow meter 351. The control device adjusts the fourth parameter, referring to FIG38, and the specific method includes the following steps S3101:

[0430] Step S3101: The control device performs PID calculations based on the current temperature value and the preset temperature range to obtain a fourth analog quantity, and adjusts the valve opening of the heat transfer oil flow meter based on the fourth analog quantity.

[0431] In this embodiment of the disclosure, the control device 2 performs PID calculations based on the current temperature value and the preset temperature range to obtain a fourth analog quantity, and adjusts the valve opening of the heat transfer oil flow meter 351 based on the fourth analog quantity.

[0432] In some embodiments of this disclosure, referring to FIG4, the first box wall 3121 of the first air box 312 inside the box 311 is provided with a visual inspection device 327. The drying data also includes appearance data obtained after the visual inspection device 327 performs image acquisition on the electrode 100. If the drying data does not meet the preset data reference benchmark, the control device 2 adjusts the initial drying parameters. Referring to FIG39, the specific method includes the following steps S3201:

[0433] Step S3201: If the appearance data does not conform to the preset appearance reference standard, the control device adjusts the first parameter, and / or the second parameter, and / or the third parameter.

[0434] In this embodiment of the disclosure, when the appearance data does not conform to the preset appearance reference benchmark, the control device 2 adjusts the first parameter, and / or the second parameter, and / or the third parameter.

[0435] In this embodiment of the disclosure, after acquiring the appearance data of the electrode 100 after the drying process, if the appearance data does not conform to the preset appearance reference standard, the control device 2 can first locate the cause of the appearance data of the electrode 100 not conforming to the preset appearance reference standard, and then adjust the first parameter, and / or the second parameter, and / or the third parameter according to the cause.

[0436] For example, if the surface of electrode 100 cracks after the drying process, the cause of the cracking can be identified as either excessively high drying temperature or excessively high airflow leading to excessively fast drying speed. Then, the parameters used to adjust the temperature and airflow among the first, second, and third parameters can be determined and adjusted accordingly. If the surface of electrode 100 is still damp and not dried after the drying process, the cause can be identified as either excessively low drying temperature or excessively low airflow leading to excessively slow drying speed. Then, the parameters used to adjust the temperature and airflow among the first, second, and third parameters can be determined and adjusted accordingly. The specific method of adjusting the first, second, and third parameters based on appearance data can be selected according to the actual situation, and this embodiment does not impose specific limitations here.

[0437] Referring to Figure 40, an exemplary process for adjusting parameters based on appearance data is provided, specifically including steps S3301 to S3301:

[0438] Step S3301: During the stable coating stage, obtain the appearance data of the electrode sheet through the visual inspection device in each oven.

[0439] Step S3302: Determine whether the appearance data conforms to the preset appearance reference standard.

[0440] Specifically, if the appearance data conforms to the preset appearance reference benchmark, proceed to step S3103; if the edge of the appearance data conforms to the preset appearance reference benchmark, proceed to step S3104.

[0441] Step S3303: Adjust the second fresh air frequency of the fresh air fan and / or the heating temperature of the heat exchange device for ovens whose appearance data does not conform to the preset appearance reference standard.

[0442] Step S3304: The appearance closed-loop adjustment of the stable coating stage is completed.

[0443] In some embodiments of this disclosure, after adjusting the initial drying parameters, the control device 2 can use the adjusted drying parameters to dry the next batch of electrode sheets. Referring to FIG41, the specific method includes the following steps S3401 to S3402:

[0444] Step S3401: After the drying process is completed, the control equipment obtains the final drying parameters of the drying equipment 1.

[0445] In this embodiment of the present disclosure, the control device 2 obtains the final drying parameters of the drying device 1 after the drying process is completed.

[0446] In this embodiment, the control device 2 can obtain stable final drying parameters of the drying device 1 after debugging the first batch of electrode sheets 100. Then, the final drying parameters can be directly applied to the next batch of electrode sheets 100. Based on this, the drying process for the same electrode sheets 100 can be completed with one debugging, avoiding the technical problem in the prior art that the drying situation needs to be manually observed and the drying device adjusted each time the electrode sheets 100 are dried, thereby reducing labor costs and electrode scrap costs.

[0447] Step S3402: When the drying process for the next batch of electrode sheets begins, the control equipment controls the drying equipment to dry the next batch of electrode sheets according to the final drying parameters.

[0448] In this embodiment of the disclosure, when the drying process for the next batch of electrode sheets 100 begins, the control device 2 controls the drying device 1 to dry the next batch of electrode sheets 100 according to the final drying parameters.

[0449] In this embodiment of the disclosure, when the control device 2 controls the drying device 1 to dry the next batch of electrode sheets 100 according to the final drying parameters, it can also continuously detect the drying process of the next batch of electrode sheets 100 so that the final drying parameters can be adjusted within a small range to achieve the best drying effect.

[0450] In this embodiment of the present disclosure, the drying system further includes a control panel. Referring to Figures 9 and 42, the control panel 300 includes at least a first drying device 3a (the lower layer of the control panel 300) and a second drying device 3b (the lower layer of the control panel 300). Each layer includes 12 drying ovens. That is, before the drying process for the electrode begins, the heating temperature range, preset negative pressure range, preset wind speed range, and preset NMP concentration range for each drying oven can be set on the control panel 300. During the drying process for the electrode, the current temperature, current wind speed, current NMP concentration, and current negative pressure value of each drying oven can be observed in real time on the control panel 300. If the current temperature, current wind speed, current NMP concentration, and current negative pressure value do not conform to the corresponding heating temperature range, preset negative pressure range, preset wind speed range, and preset NMP concentration range, the initial drying parameters are adjusted based on the current temperature, current wind speed, current NMP concentration, and current negative pressure value to achieve the best drying effect.

[0451] This disclosure provides a drying method applied to a drying system, which includes a drying device and a control device. The method includes: the drying device drying an electrode sheet according to initial drying parameters; the control device acquiring drying data of the electrode sheet during the drying process at preset time intervals after the drying process begins; and the control device adjusting the initial drying parameters when the drying data does not conform to a preset data reference standard, until the drying process is completed. By adopting the above implementation scheme, this disclosure, through the control device periodically adjusting the initial drying parameters, keeps the drying data within the preset data reference standard as much as possible throughout the drying process, thereby improving the uniformity of the drying effect and enhancing the quality of the electrode sheet.

[0452] This disclosure also provides a computer program product, including a computer program or instructions, which, when executed by one or more processors, implement the steps in the drying method described above.

[0453] This disclosure also provides a computer-readable storage medium storing a computer program thereon. The computer-readable storage medium stores one or more programs, which can be executed by one or more processors and applied to a drying system. The computer program implements the drying method described above.

[0454] It should be noted that the descriptions of the storage medium and device embodiments above are similar to those of the method embodiments above, and have similar beneficial effects. For technical details not disclosed in the storage medium and device embodiments of this disclosure, please refer to the descriptions of the method embodiments of this disclosure for understanding.

[0455] The aforementioned processor can be at least one of the following: Application Specific Integrated Circuit (ASIC), Digital Signal Processor (DSP), Digital Signal Processing Device (DSPD), Programmable Logic Device (PLD), Field Programmable Gate Array (FPGA), Central Processing Unit, Controller, Microcontroller, and Microprocessor. It is understood that other electronic devices can also implement the functions of the aforementioned processor, and this disclosure does not specifically limit the specific implementation.

[0456] The aforementioned computer storage media / memory can be read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), magnetic random access memory (FRAM), flash memory, magnetic surface memory, optical disc, or compact disc read-only memory (CD-ROM), etc.; or it can be various terminals that include one or any combination of the above-mentioned memories, such as mobile phones, computers, tablet devices, personal digital assistants, etc.

[0457] It should be understood that the phrase "an embodiment" or "one embodiment" throughout the specification means that a specific feature, structure, or characteristic related to the embodiment is included in at least one embodiment of this disclosure. Therefore, "in one embodiment" or "one embodiment" appearing throughout the specification does not necessarily refer to the same embodiment. Furthermore, these specific features, structures, or characteristics can be combined in any suitable manner in one or more embodiments. It should be understood that in the various embodiments of this disclosure, the sequence numbers of the above steps / processes do not imply a sequential order of execution; the execution order of each step / process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this disclosure. The sequence numbers of the above embodiments of this disclosure are merely descriptive and do not represent the superiority or inferiority of the embodiments.

[0458] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0459] In the several embodiments provided in this disclosure, it should be understood that the disclosed devices and methods can be implemented in other ways. The device embodiments described above are merely illustrative. For example, the division of units is only a logical functional division, and in actual implementation, there may be other division methods, such as: multiple units or components may be combined, or integrated into another system, or some features may be ignored or not executed. In addition, the coupling, direct coupling, or communication connection between the various components shown or discussed may be through some interfaces, and the indirect coupling or communication connection between devices or units may be electrical, mechanical, or other forms.

[0460] The units described above as separate components may or may not be physically separate. The components shown as units may or may not be physical units. They may be located in one place or distributed across multiple network units. Some or all of the units may be selected to achieve the purpose of this embodiment according to actual needs.

[0461] In addition, each functional unit in the various embodiments of this disclosure can be integrated into one processing unit, or each unit can be a separate unit, or two or more units can be integrated into one unit; the integrated unit can be implemented in hardware or in the form of hardware plus software functional units.

[0462] Those skilled in the art will understand that all or part of the steps of the above method embodiments can be implemented by hardware related to program instructions. The aforementioned program can be stored in a computer-readable storage medium. When the program is executed, it performs the steps of the above method embodiments. The aforementioned storage medium includes various media that can store program code, such as mobile storage devices, read-only memory (ROM), magnetic disks, or optical disks.

[0463] Alternatively, if the integrated units described above are implemented as software functional modules and sold or used as independent products, they can also be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this disclosure, or the part that contributes to related technologies, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the methods of the various embodiments of this disclosure. The aforementioned storage medium includes various media capable of storing program code, such as mobile storage devices, ROMs, magnetic disks, or optical disks.

[0464] The above are merely embodiments of this disclosure, but the scope of protection of this disclosure is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this disclosure should be included within the scope of protection of this disclosure.

Claims

1. A drying apparatus, comprising: At least two connected ovens are provided, each oven having a drying area, during which the electrode is dried as it passes through each oven. Each oven is equipped with a pressure detection device, which is used to detect the pressure value inside the oven as a partial pressure value. Each oven is provided with a fresh air inlet for fresh air to enter and an exhaust vent for gas to exit the oven. The fresh air duct is connected to the fresh air inlet of each oven via a pipe. The fresh air duct is equipped with a main fresh air fan, and each oven is equipped with a fresh air valve at its fresh air inlet. The exhaust duct is provided with exhaust ports of each oven connected to the exhaust duct via pipes. The exhaust duct is equipped with a main exhaust fan, and each oven is equipped with an exhaust valve at its exhaust port. The NMP recovery system is used to recover N-methylpyrrolidone generated during the drying process of the electrodes in the drying zones of each of the ovens. The fresh air main duct is connected to the outlet of the NMP recovery system, and the exhaust main duct is connected to the inlet of the NMP recovery system. The oven whose partial air pressure value is not within the preset partial negative pressure value range is designated as the oven to be adjusted. In the case of at least one oven to be adjusted, the output power of the main fresh air fan and the main exhaust fan and the opening degree of the fresh air valve and the exhaust air valve of the oven to be adjusted are adjusted so that the partial air pressure value of the oven to be adjusted is within the preset partial negative pressure value range.

2. The drying apparatus according to claim 1, wherein, Each of the ovens is equipped with an NMP concentration measuring device at its exhaust vent. The NMP concentration measuring device is used to detect the NMP concentration value passing through the exhaust vent. Each of the ovens is equipped with a circulating fan, which drives the gas that is circulated back from the drying area and the gas that is circulated from the fresh air inlet to flow toward the drying area. The oven whose NMP concentration value is not within the preset NMP concentration value range is designated as the oven to be adjusted. In the case of at least one oven to be adjusted, the output power of the circulating fan and the opening of the fresh air valve and the exhaust air valve of the oven to be adjusted are adjusted so that the NMP concentration value of the oven to be adjusted is within the preset NMP concentration value range.

3. The drying apparatus according to claim 2, wherein, Each of the ovens is equipped with an air inlet speed measuring device, which is used to detect the wind speed value of the gas after the circulating air and the fresh air converge. If the wind speed value measured by the air inlet speed measuring device is not within the preset wind speed range, adjust the circulating fan so that the wind speed value measured by the air inlet speed measuring device is within the preset wind speed range.

4. The drying apparatus according to claim 3, wherein, Each of the ovens is equipped with a fresh air fan and a fresh air speed measuring device at its fresh air inlet. The fresh air fan can adjust the air speed at the fresh air inlet, and the fresh air speed measuring device can detect the air speed at the fresh air inlet. Each of the ovens is equipped with an exhaust fan and an exhaust speed measuring device at its exhaust vent. The exhaust fan can adjust the air speed at the exhaust vent, and the exhaust speed measuring device detects the air speed at the exhaust vent. In the presence of at least one of the aforementioned pressure-adjustable ovens, the output power of the main fresh air fan and the main exhaust fan, the opening degree of the fresh air valve and the exhaust valve of the pressure-adjustable oven, and the output power of the fresh air fan and the exhaust fan are adjusted so that the partial pressure value of the pressure-adjustable oven is within the preset partial negative pressure value range. In the presence of at least one of the ovens with the concentration to be adjusted, the output power of the circulating fan, the opening degree of the fresh air valve and the exhaust air valve of the oven with the concentration to be adjusted, and the output power of the fresh air fan and the exhaust fan are adjusted so that the NMP concentration value of the oven with the concentration to be adjusted is within the preset NMP concentration value range.

5. The drying apparatus according to claim 4, wherein, Each of the aforementioned ovens is equipped with a heat exchange device, which is used to heat the gas after the circulating air and the fresh air converge. In the presence of at least one of the ovens with the concentration to be adjusted, the heating temperature of the heat exchange device of the oven with the concentration to be adjusted is adjusted so that the NMP concentration value of the oven with the concentration to be adjusted is within the preset NMP concentration value range.

6. The drying apparatus according to claim 5, wherein, In the presence of at least one of the ovens with the concentration to be adjusted, the output power of the main fresh air fan and / or the main exhaust fan is adjusted so that the NMP concentration value of the oven with the concentration to be adjusted is within the preset NMP concentration value range.

7. The drying apparatus according to claim 5, wherein, The exhaust manifold is equipped with a total exhaust NMP concentration measuring device, which is used to detect the total NMP concentration of the gas passing through the exhaust manifold. When at least one of the ovens with the concentration to be adjusted exists, and the total NMP concentration value is not within the preset total NMP concentration value range, the output power of the circulating fan and the heating temperature of the heat exchange device of the oven with the concentration to be adjusted are first adjusted to make the total NMP concentration value within the preset total NMP concentration value range. Then, the output power of the fresh air fan and the exhaust fan, the opening degree of the fresh air valve and the exhaust air valve, and the heating temperature of the heat exchange device of the oven with the concentration to be adjusted are adjusted to make the partial NMP concentration value of the oven with the concentration to be adjusted within the preset partial NMP concentration value range.

8. The drying apparatus according to any one of claims 4 to 7, wherein, The exhaust main is equipped with a total pressure detection device, which is used to detect the total air pressure value inside the exhaust main. When at least one of the pressure-adjustable ovens exists and the total pressure value is not within the preset total negative pressure range, the output power of the main fresh air fan and the main exhaust fan is first adjusted to bring the total pressure value within the preset total negative pressure range. Then, the output power of the fresh air fan and the exhaust fan of the pressure-adjustable oven, as well as the opening degree of the fresh air valve and the exhaust air valve, are adjusted to bring the partial pressure value within the preset partial negative pressure range.

9. The drying apparatus according to any one of claims 1 to 8, wherein, The main fresh air duct is equipped with a main fresh air velocity measuring device. During the adjustment of the main fresh air fan, the main fresh air velocity measuring device detects the air velocity in the main fresh air duct. The exhaust manifold is equipped with a main exhaust speed measuring device, which detects the air velocity inside the exhaust manifold during the adjustment of the main exhaust fan.

10. The drying apparatus according to claim 5, wherein, Each of the aforementioned ovens includes a chamber and a first air box and a second air box disposed within the chamber. The first air box and the second air box are disposed opposite to each other, and the drying area is defined between them. The first air box is provided with a first air inlet for gas to enter, and the second air box is provided with a second air inlet for gas to enter. The first air box has a first box wall facing the second air box, and the first box wall is provided with a plurality of first air nozzles with outlets facing the drying area. The first air nozzles are used to discharge the gas in the first air box toward the electrode. The second air box has multiple second air nozzles on its wall facing the first air box, with outlets pointing towards the drying area. These second air nozzles are used to allow gas from the second air box to be discharged towards the electrode. The housing is provided with a fresh air inlet and an exhaust outlet. The fresh air inlet is connected to the first air inlet of the first air box and the second air inlet of the second air box, and the exhaust outlet is connected to the drying area.

11. The drying apparatus according to claim 10, wherein, The chamber is equipped with a return air duct, and a circulating fan is installed within the return air duct. The fresh air inlet and the exhaust outlet are respectively connected to the return air duct. The circulating fan drives the gas in the drying area through the return air duct and then through the exhaust outlet, causing some of the gas to be discharged through the exhaust outlet. It also drives the remaining gas in the return air duct and the fresh air supplied from the fresh air inlet through the return air duct into the first air inlet and the second air inlet. The heat exchange device and the air box inlet speed measuring device are installed in the return air duct between the fresh air inlet and the first air inlet and the second air inlet.

12. The drying apparatus according to claim 11, wherein, The first air box is equipped with a first air inlet valve at its first air inlet, and the second air box is equipped with a second air inlet valve at its second air inlet. During the process of adjusting the output power of the circulating fan, the opening degree of the first air inlet valve and / or the second air inlet valve is adjusted.

13. The drying apparatus according to claim 11, wherein, The first chamber wall is provided with a return air nozzle for the gas in the drying area to flow back to the return air duct.

14. The drying apparatus according to claim 11, wherein, A visual inspection device is provided on the outer side of the first box wall of the first air box, and the visual inspection device is used to inspect the appearance of the electrode sheet located in the drying area.

15. The drying apparatus according to claim 14, wherein, The visual inspection device is connected to the outside of the first box wall via a mounting assembly, the mounting assembly being configured to adjust the position of the visual inspection device along the width direction of the electrode.

16. A coating machine, comprising: The first coating head is used to coat the first surface of the substrate to form an electrode sheet; A first drying apparatus and a second drying apparatus formed by the drying apparatus according to any one of claims 1 to 15, wherein the first drying apparatus is disposed downstream of the first coating head and is used to dry the electrode sheet with the first surface facing upward; The second coating head is located downstream of the first drying device and is used to coat the second surface of the electrode sheet. A climbing mechanism is located downstream of the second coating head and upstream of the second drying device. The climbing mechanism is used to support the electrode sheet from one side of the first surface of the electrode sheet and pull the electrode sheet so that the electrode sheet enters the second drying device with the second surface facing upward. The second drying device is used to dry the electrode sheet with the second surface facing upward.

17. A drying method using a drying apparatus, the drying apparatus comprising a fresh air main duct, an exhaust air main duct, and at least two interconnected drying ovens, each drying oven having a drying area, wherein the electrode is dried as it passes through each of the drying ovens, each drying oven is equipped with a pressure detection device for detecting the pressure value inside the drying oven as a partial pressure value, each drying oven having a fresh air inlet for fresh air intake and an exhaust air outlet for exhausting gas from the drying oven; the fresh air inlets of each drying oven are respectively connected to the fresh air main duct via pipes. The main fresh air duct is equipped with a main fresh air fan, and each of the ovens has a fresh air valve at its fresh air inlet; the exhaust outlets of each of the ovens are connected to the main exhaust duct via pipes, the main exhaust duct is equipped with a main exhaust fan, and each of the ovens has an exhaust valve at its exhaust outlet; the NMP recovery system is used to recover N-methylpyrrolidone generated during the drying process of the electrode sheets in the drying area of ​​each of the ovens, the main fresh air duct is connected to the outlet of the NMP recovery system, and the main exhaust duct is connected to the inlet of the NMP recovery system; The drying method includes: In the air pressure adjustment step, the ovens whose partial air pressure values ​​measured by the air pressure detection device are not within the preset partial negative pressure value range are designated as air pressure ovens to be adjusted. If there is at least one such air pressure oven to be adjusted, the output power of the main fresh air fan and the main exhaust fan, as well as the opening degree of the fresh air valve and the exhaust air valve of the air pressure oven to be adjusted, are adjusted so that the partial air pressure value of the air pressure oven to be adjusted is within the preset partial negative pressure value range.

18. The drying method according to claim 17, wherein, Each of the ovens is equipped with a circulating fan, which drives the gas after the circulating air returning from the drying area and the fresh air entering from the fresh air inlet to flow toward the drying area; each of the ovens is equipped with an air box inlet speed measuring device, which is used to detect the wind speed value of the circulating air and the gas after the fresh air enters. The drying method further includes, after the air pressure regulation step: In the wind speed adjustment step, if the wind speed value measured by the air inlet speed measuring device of the air box is not within the preset wind speed value range, the circulating fan is adjusted so that the wind speed value measured by the air inlet speed measuring device of the air box is within the preset wind speed value range.

19. The drying method according to claim 18, wherein, Each of the ovens is equipped with an NMP concentration measuring device at its exhaust vent. The NMP concentration measuring device is used to detect the NMP concentration value passing through the exhaust vent. The drying method further includes, after the wind speed adjustment step: In the concentration adjustment step, the ovens whose NMP concentration values ​​measured by the NMP concentration measuring device are not within the preset NMP concentration value range are designated as ovens to be adjusted. If at least one of the ovens to be adjusted exists, the output power of the circulating fan and the opening degree of the fresh air valve and the exhaust air valve of the oven to be adjusted are adjusted so that the NMP concentration value of the oven to be adjusted is within the preset NMP concentration value range.

20. The drying method according to claim 19, wherein, Each of the ovens is equipped with a fresh air fan at its fresh air inlet, which is used to adjust the airflow speed at the fresh air inlet; each of the ovens is equipped with an exhaust fan at its exhaust outlet, which is used to adjust the airflow speed at the exhaust outlet. In the air pressure regulation step, the output power of the fresh air fan and the exhaust fan of the oven whose air pressure is to be regulated is also adjusted. In the concentration adjustment step, the output power of the fresh air fan and the exhaust fan of the oven whose concentration is to be adjusted is also adjusted.

21. The drying method according to claim 20, wherein, Each of the ovens is equipped with a heat exchange device, which is used to heat the temperature of the gas after the circulating air and the fresh air converge. In the concentration adjustment step, the heating temperature of the heat exchange device of the oven with the concentration to be adjusted is also adjusted.

22. The drying method according to claim 20 or 21, wherein, In the concentration adjustment step, the output power of the main fresh air fan and / or the main exhaust fan is also adjusted.

23. The drying method according to claim 21, wherein, The exhaust manifold is equipped with a total exhaust NMP concentration measuring device, which is used to detect the total NMP concentration value of the gas passing through the exhaust manifold. The concentration adjustment step includes: The total concentration adjustment step involves adjusting the output power of the circulating fan and the heating temperature of the heat exchange device of the oven to be adjusted when at least one oven with the concentration to be adjusted exists and the total NMP concentration value is not within the preset total NMP concentration value range, so that the total NMP concentration value is within the preset total NMP concentration value range. In the concentration adjustment step, the output power of the fresh air fan and the exhaust fan of the oven to be adjusted, the opening degree of the fresh air valve and the exhaust air valve, and the heating temperature of the heat exchange device are adjusted so that the NMP concentration value of the oven to be adjusted is within the preset NMP concentration value range.

24. The drying method according to any one of claims 20 to 23, wherein, The exhaust main is equipped with a total pressure detection device, which is used to detect the total air pressure value in the exhaust main. The pressure regulation step includes: In the total air pressure adjustment step, when there is at least one of the ovens whose air pressure needs to be adjusted and the total air pressure value is not within the preset total negative pressure value range, the output power of the total fresh air fan and the total exhaust fan is adjusted so that the total air pressure value is within the preset total negative pressure value range. The air pressure adjustment step involves adjusting the output power of the fresh air fan and the exhaust fan of the oven to be adjusted, as well as the opening degree of the fresh air valve and the exhaust air valve, so that the air pressure value is within the preset negative pressure value range.

25. The drying method according to any one of claims 19 to 24, wherein, Each of the ovens is equipped with a visual inspection device in its drying zone, which is used to inspect the appearance of the electrode sheet after it passes through the drying zone. The drying method further includes: The visual feedback step involves performing the air pressure adjustment step, and / or the wind speed adjustment step, and / or the concentration adjustment step if the appearance measured by the visual inspection device does not conform to the preset appearance reference standard.

26. The drying method according to claim 17, wherein, The drying method further includes: After the drying process of a batch of electrode sheets is completed, the final drying parameters are obtained. The final drying parameters include the final output power of the main fresh air fan and the main exhaust fan, and the final opening degree of the fresh air valve and the exhaust air valve of the pressure-adjustable oven. When the drying process for the next batch of electrode sheets begins, the drying device dries the next batch of electrode sheets according to the final drying parameters.

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