Lithium battery pole piece hot rolling device and rolling method thereof

Abstract

The invention discloses a lithium battery pole piece hot rolling device and a rolling method thereof, and relates to the technical field of lithium battery manufacturing. The lithium battery pole piece hot rolling device is provided with two compression rollers which are symmetrical up and down, a cross beam is movably inserted in the central axis positions of the compression rollers in a penetrating mode, and a heat insulation box fixedly connected with the cross beam is arranged in the direction where the two compression rollers are close to each other; by means of electric heating of the electric heating assembly and covering of the heat insulation box on the close positions in the upper and lower compression rollers, in the rolling process of the compression rollers, heating can be concentrated on the contact portions when the compression rollers roll the lithium battery pole piece, heating can be more concentrated, the hot rolling effect of the lithium battery pole piece is improved, and the service life of the lithium battery pole piece is prolonged. And the heating range of the compression roller can be effectively reduced, the reduction of heat energy loss is facilitated, and the energy-saving hot rolling production of the lithium battery pole piece is realized to a certain extent.

Description

Technical Field

[0001] This invention relates to the field of lithium battery manufacturing technology, and in particular to a lithium battery electrode hot rolling device and rolling method. Background Technology

[0002] With the increasing number of new energy electric vehicles, lithium batteries, as energy storage units for electric vehicles, have broad market prospects. In the manufacturing process of lithium batteries, lithium battery electrodes are formed by mixing positive and negative electrode active materials, conductive agents and binders in a certain proportion to form a slurry and then coating it onto aluminum or copper foil. This results in a relatively loose structure of the initially solidified lithium battery electrodes. To improve the quality of lithium batteries, the rolling process of lithium battery electrodes is particularly important.

[0003] During the rolling process of lithium battery electrodes, hot rolling can effectively improve the connection strength of the electrodes and increase the energy density of the lithium battery after production. Traditionally, the entire pressure roller is heated during hot rolling of lithium battery electrodes. In this heating mode, the heating area covers the entire surface of the pressure roller. Although this can ensure the uniformity of heating of the electrode during the rolling process to a certain extent, the large area of ​​heating means that a lot of heat energy needs to be consumed to maintain the temperature of the pressure roller. In the actual hot rolling process, the contact area between the lithium battery electrode and the pressure roller is limited, and a lot of heat energy is difficult to act on the lithium battery electrode, which easily leads to heat energy waste. In addition, the heating element operates at high power continuously, which directly leads to a large amount of electrical energy loss and significantly increases the production cost of hot rolling of lithium battery electrodes.

[0004] To address these issues, a lithium battery electrode hot rolling device and its rolling method are proposed to solve some of the problems existing in the prior art. Summary of the Invention

[0005] The purpose of this invention is to address the shortcomings of existing technologies in the hot rolling process of lithium battery electrodes, which requires heating the entire pressure roller, resulting in significant heat loss and energy waste. The invention proposes a hot rolling device and rolling method for lithium battery electrodes.

[0006] To address the problems existing in the prior art, the present invention adopts the following technical solution:

[0007] A lithium battery electrode hot rolling device includes a first base, on which a vertically arranged electric lift is mounted, and a lifting platform is fixed on the sliding end of the electric lift. Horizontally arranged pressure rollers are rotatably mounted inside both the first base and the lifting platform. The two pressure rollers are symmetrically arranged vertically and rotate relative to each other. Lithium battery electrodes are inserted between the upper and lower pressure rollers. A crossbeam is movably inserted at the central axis position inside each pressure roller. The lower crossbeam is fixedly connected to the first base, and the upper crossbeam is fixedly connected to the lifting platform. A heat insulation box is fixed on the crossbeam and slides against the inner end wall of the pressure roller. The lower heat insulation box faces the upper inner end wall of the lower pressure roller, and the upper heat insulation box faces the lower inner end wall of the upper pressure roller. An electric heating component is fixed inside the heat insulation box.

[0008] Preferably, the end of the pressure roller is fixed with a first bevel tooth, a vertically arranged spline shaft is rotatably arranged inside the first machine base, and a second bevel tooth that meshes with the lower first bevel tooth is fixed on the spline shaft. A spline cylinder is slidably sleeved on the spline shaft, and a third bevel tooth that meshes with the upper first bevel tooth is fixed on the spline cylinder.

[0009] Preferably, a second base is provided in front of the first base, and two preheating rollers rotate inside the second base. The interior of the preheating rollers is configured as a hollow structure. The lithium battery electrode sheets pass around the two preheating rollers in sequence, and the front and back sides of the lithium-ion electrode sheets are respectively attached to the outer surfaces of the two preheating rollers. Both ends of the crossbeam are connected to the interior of the heat insulation box. One end of the crossbeam is connected to an air inlet pipe, and the other end of the crossbeam is connected to a first transfer pipe. The other end of the first transfer pipe is rotatably connected to one end of the preheating roller, and the other end of the preheating roller is rotatably connected to a second transfer pipe.

[0010] Preferably, the two preheating rollers are arranged symmetrically above and below each other, and the second base is rotatably installed with guide rollers located on both sides in the middle of the two preheating rollers. The lithium battery electrode sheet is guided by the two preheating rollers and the two guide rollers to form an "8" shape.

[0011] Preferably, the ends of the two preheating rollers are fixed with meshing gears, the upper preheating roller is connected to the rear guide roller by a first sprocket drive assembly, and the lower preheating roller is connected to the front guide roller by a second sprocket drive assembly.

[0012] Preferably, both the upper and lower pressure rollers are fitted with heat insulation covers on their outer sides, and a heat insulation box that is fitted on the outer sides of the two preheating rollers and the two guide rollers is fixed inside the second machine base.

[0013] Preferably, an air blowing box located in front of the heat preservation box is fixed on the second base, the lithium battery electrode is movably inserted in the middle of the air blowing box, and longitudinally arranged airflow channels are fixed on the left and right sides of the air blowing box, and the rear end of the airflow channel is fixedly connected to the second adapter pipe.

[0014] Preferably, a number of symmetrically arranged guide plates are fixed on the inner end walls of the upper and lower sides of the air blowing box, and the guide plates are inclinedly arranged inside the air blowing box. One end of the guide plate points to the front opening of the air blowing box, and the other end of the guide plate extends into the airflow channel. The numerous guide plates are evenly distributed from back to front, and the length of the part extending into the airflow channel gradually increases.

[0015] Preferably, the top of the rear guide roller is flush with the top of the lower pressure roller, and the bottom of the front guide roller is flush with the center plane inside the air blowing box.

[0016] Preferably, a method for rolling lithium battery electrodes includes the following steps:

[0017] S1. Preheating: Hot air enters from the rear end of the airflow channel through the second adapter pipe and flows from back to front in the airflow channel. Under the guidance of numerous guide plates, it is evenly dispersed in the air blowing box to preheat the lithium battery electrode sheets passing through the air blowing box and simultaneously clean the front and back sides of the lithium battery electrode sheets with air blowing. The lithium battery electrode sheets are heated to 40°C after passing through the air blowing box.

[0018] S2. Second-stage preheating: During the lithium battery electrode conveying process, the electrode passes around two preheating rollers and two guide rollers in an orderly manner. Simultaneously, the hot air enters the preheating roller through the first transfer pipe and heats the preheating roller to 80°C. The two preheating rollers then tightly adhere to the front and back sides of the lithium battery electrode in sequence, raising the temperature of the lithium battery electrode after the first stage of preheating from 40°C to 80°C.

[0019] S3. Three-stage direct heating: The electric heating component inside the heat insulation box is powered on and starts heating the bottom of the upper pressure roller and the top of the lower pressure roller to 140℃. The lithium battery electrode sheet, which has been preheated in the second stage, is conveyed between the upper and lower pressure rollers. Through the contact between the lithium battery electrode sheet and the similar outer surfaces of the upper and lower pressure rollers, the temperature of the lithium battery electrode sheet is rapidly increased from 80℃ to 140℃.

[0020] S4. Roll forming: The lithium battery electrode sheet heated to 140℃ is placed between two upper and lower pressure rollers. The distance between the two pressure rollers is adjusted by an electric lifting machine. With the relative rotation of the two pressure rollers, the rolling process is completed during the conveying of the lithium battery electrode sheet.

[0021] Compared with the prior art, the beneficial effects of the present invention are:

[0022] 1. In this invention, two symmetrical pressure rollers are provided. A crossbeam is movably inserted at the central axis of the pressure rollers. A heat insulation box fixedly connected to the crossbeam is provided in the direction where the two pressure rollers approach each other. With the help of electric heating of the electric heating component and the coverage of the heat insulation box on the close positions inside the upper and lower pressure rollers, the heating can be concentrated at the contact part when the pressure rollers roll the lithium battery electrode during the rolling process. This not only makes the heating more concentrated and improves the effect of hot rolling of lithium battery electrode, but also effectively reduces the heating range of the pressure roller, which is conducive to reducing heat loss. To a certain extent, it realizes the energy-saving hot rolling production of lithium battery electrode.

[0023] 2. In this invention, by setting two preheating rollers to contact the front and back sides of the lithium battery electrode respectively, the heat inside the two preheating rollers can be used to heat and preheat both sides of the lithium battery electrode simultaneously. With the guidance of two guide rollers, the contact area between the lithium battery electrode and the outer surface of the preheating rollers can be greatly increased, making the heating of the lithium battery electrode more uniform and efficient during the preheating process. To a certain extent, this improves the uniformity and stability of the lithium battery electrode being preheated by the two preheating rollers.

[0024] 3. In this invention, by placing the air-blowing box in front of the two preheating rollers, the lithium battery electrode sheets pass through the air-blowing box before being preheated by the preheating rollers. The airflow is guided by the connection of the first and second transfer pipes, allowing the airflow heated by the residual heat in the insulation box to be gradually introduced into the preheating rollers and the air-blowing box. With the cooperation of the air-blowing box, the preheating rollers, and the electric heating components, progressive heating is formed, which can effectively improve the uniformity of heating of the lithium battery electrode sheets and avoid damage to the lithium battery electrode sheets due to sudden temperature rise during hot rolling. At the same time, during air-blowing preheating in the air-blowing box, the front and back sides of the lithium battery electrode sheets can also be cleaned by air-blowing, preventing impurities from adhering to the lithium battery electrode sheets during hot rolling and causing damage to the lithium battery electrode sheets after rolling. This improves the stability of the device during operation to a certain extent. Attached Figure Description

[0025] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this application, illustrate exemplary embodiments of the invention and, together with their description, serve to explain the invention and do not constitute an undue limitation thereof. In the drawings:

[0026] Figure 1 This is a perspective view of the present invention;

[0027] Figure 2 This is a perspective view of the structure on the first base of the present invention;

[0028] Figure 3 This is a perspective view of the first bevel tooth, spline shaft, second bevel tooth, and third bevel tooth of the present invention.

[0029] Figure 4 This is an exploded view of the pressure roller and crossbeam of the present invention;

[0030] Figure 5 This is a perspective view of the two preheating rollers and two guide rollers of the present invention;

[0031] Figure 6 This is a perspective view of the air blowing box, airflow channel, and guide plate of the present invention;

[0032] Figure 7 This is a top view of the present invention;

[0033] Figure 8 For the present invention Figure 7 Sectional view at point AA;

[0034] Figure 9 For the present invention Figure 7 Sectional view at point BB;

[0035] Figure 10 For the present invention Figure 7 Sectional view at CC;

[0036] Figure 11 This is a side view of the present invention;

[0037] Figure 12 For the present invention Figure 11 Sectional view at point DD;

[0038] Figure 13 For the present invention Figure 11 Sectional view at EE.

[0039] Number in the diagram:

[0040] 1. First machine base; 101. Electric lifting platform; 102. Lifting platform; 103. Pressure roller; 104. First bevel gear; 105. Splined shaft; 106. Second bevel gear; 107. Splined cylinder; 108. Third bevel gear;

[0041] 2. Crossbeam; 201. Insulation box; 202. Electric heating assembly; 203. Insulation cover;

[0042] 3. Second machine base; 301. Preheating roller; 302. Guide roller; 303. Gear; 304. First sprocket drive assembly; 305. Second sprocket drive assembly; 306. Insulation box;

[0043] 4. Intake pipe; 401. First adapter pipe; 402. Second adapter pipe;

[0044] 5. Air blowing box; 501. Airflow channel; 502. Drainage plate. Detailed Implementation

[0045] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0046] Example: This example provides a lithium battery electrode hot rolling device, see [link to example]. Figure 1 - Figure 13 Specifically, it includes a first base 1, on which a vertically arranged electric lift 101 is mounted, and a lifting platform 102 is fixed to the sliding end of the electric lift 101. Horizontally arranged pressure rollers 103 are rotatably mounted inside both the first base 1 and the lifting platform 102. The two pressure rollers 103 are symmetrically arranged vertically and rotate relative to each other. Lithium battery electrodes are inserted between the upper and lower pressure rollers 103. A first bevel tooth 104 is fixed to the end of each pressure roller 103. A vertically arranged splined shaft 105 rotates within the first base 1, and a second bevel tooth 106 is fixed on the splined shaft 105 to mesh with the lower first bevel tooth 104. A splined cylinder 107 is slidably sleeved on the key shaft 105, and a third bevel tooth 108 that meshes with the upper first bevel tooth 104 is fixed on the splined cylinder 107. A crossbeam 2 is movably inserted at the central axis position inside the pressure roller 103. The lower crossbeam 2 is fixedly connected to the first machine base 1, and the upper crossbeam 2 is fixedly connected to the lifting platform 102. A heat insulation box 201 that slides against the inner end wall of the pressure roller 103 is fixed on the crossbeam 2. The lower heat insulation box 201 faces the upper inner end wall of the lower pressure roller 103, and the upper heat insulation box 201 faces the lower inner end wall of the upper pressure roller 103. An electric heating component 202 is fixed inside the heat insulation box 201.

[0047] In use, one of the pressure rollers 103 is connected to an external servo motor, which drives the pressure roller 103 to rotate. Taking the lower pressure roller 103 as an example, the rotation of the lower pressure roller 103 will drive the lower first bevel tooth 104 to rotate. With the meshing of the lower first bevel tooth 104 and the second bevel tooth 106, the spline shaft 105 is driven to rotate, which in turn drives the third bevel tooth 108, which is sleeved on the spline cylinder 107 outside the spline shaft 105, to rotate synchronously. With the meshing of the third bevel tooth 108 and the upper first bevel tooth 104, the upper pressure roller is driven. The upper and lower pressure rollers 103 rotate synchronously, with the upper roller rotating counterclockwise and the lower roller rotating clockwise. The lithium battery electrode sheet to be rolled is conveyed from the front to between the upper and lower pressure rollers 103. During the backward conveying process, it is squeezed by the rotation of the upper and lower pressure rollers 103. The lifting platform 102 is moved up and down by the electric lifting machine 101, which can adjust the distance between the upper and lower pressure rollers 103. This allows the device to flexibly adjust the degree of rolling of the lithium battery electrode sheet according to the processing requirements.

[0048] During the process of pressing the lithium battery electrode sheets by synchronously rotating the upper and lower pressure rollers 103, the electric heating component 202 installed in the heat insulation box 201 will be energized and start to perform electric heating operation. Since the upper heat insulation box 201 covers the lower inner end wall of the upper pressure roller 103, and the lower heat insulation box 201 covers the upper inner end wall of the lower pressure roller 103, the electric heating of the electric heating component 202 in the upper heat insulation box 201 can be concentrated on the lower part of the upper pressure roller 103, and the electric heating of the electric heating component 202 in the lower heat insulation box 201 can be concentrated on the lower part of the upper pressure roller 103. Above the lower pressure roller 103, compared to the existing technology that heats the entire pressure roller 103, this application places the heat insulation box 201 inside the pressure roller 103 and allows it to rotate relative to the pressure roller 103. This enables the electric heating component 202 inside the heat insulation box 201 to concentrate its heating on the rolling part of the pressure roller 103 when rolling the lithium battery electrode. This not only makes the heating more concentrated and improves the effect of hot rolling of the lithium battery electrode, but also effectively reduces the area of ​​the pressure roller 103 that is heated, which helps to reduce heat loss and achieves energy-saving hot rolling production to a certain extent.

[0049] In the specific implementation process, such as Figure 1 , Figure 11 and Figure 12 As shown, a second base 3 is provided in front of the first base 1, and two preheating rollers 301 rotate inside the second base 3. The interior of the preheating rollers 301 is hollow. The lithium battery electrode sheets pass around the two preheating rollers 301 in sequence, and the front and back sides of the lithium-ion electrode sheets are respectively attached to the outer surfaces of the two preheating rollers 301. Both ends of the crossbeam 2 are connected to the interior of the heat insulation box 201. One end of the crossbeam 2 is connected to the air inlet pipe 4, and the other end of the crossbeam 2 is connected to the first adapter pipe 401. The other end of the first adapter pipe 401 is rotatably connected to one end of the preheating roller 301, and the other end of the preheating roller 301 is rotatably connected to the second adapter pipe 402.

[0050] When the device is in use, the left end of the heat insulation box 201 is connected to the left end of the crossbeam 2, and the right end of the heat insulation box 201 is connected to the right end of the crossbeam 2. An air pump is connected to the air inlet pipe 4. After the air pump is powered on and started, air is supplied to the heat insulation box 201 through the air inlet pipe 4. The edge of the heat insulation box 201 slides against the inner end wall of the pressure roller 103. A sealing structure is provided at the contact position to prevent the airflow from leaking into the pressure roller 103 through the contact position, thus ensuring the stability of the airflow in the heat insulation box 201. When the airflow flows in the heat insulation box 201, it can not only conduct residual heat, but also effectively improve the heat conduction uniformity of the part of the pressure roller 103 covered by the heat insulation box 201, further improving the accuracy of temperature control when the device heats and rolls lithium battery electrodes.

[0051] The airflow carrying the residual heat from the electric heating component 202 inside the heat insulation box 201 is discharged through the first transfer pipe 401 rotatably connected to the other end of the crossbeam 2, and then enters the preheating roller 301 through the first transfer pipe 401, and finally exits through the second transfer pipe 402. The airflow blows excess residual heat generated by the electric heating component 202 inside the heat insulation box 201 into the preheating roller 301, using this residual heat to heat the area inside the preheating roller 301. Because the preheating roller 301 is located in front of the first machine base 1, the lithium battery electrode sheets will bypass the two preheating rollers 301 before entering between the upper and lower pressure rollers 103. Through the sequential contact between the lithium battery electrode sheets and the two preheating rollers 301, the residual heat can be used to preheat the lithium battery electrode sheets before hot rolling, making it easier for the lithium battery electrode sheets to be heated to a suitable temperature when conveyed between the upper and lower pressure rollers 103 for hot rolling. This not only reduces the waste of heat energy.

[0052] This achieves energy-saving production. At the same time, by preheating, the difficulty of heating the lithium battery electrode to the final temperature at the pressure roller 103 can be reduced, and the residence time of the lithium battery electrode between the upper and lower pressure rollers 103 can be reduced, which is conducive to improving the overall processing efficiency.

[0053] Meanwhile, when using the preheating roller 301 to preheat the lithium battery electrode, two preheating rollers 301 are set to contact the front and back sides of the lithium battery electrode respectively. The heat in the two preheating rollers 301 is used to heat the front and back sides of the lithium battery electrode simultaneously, making the lithium battery electrode heatd more evenly during the preheating process. This improves the uniformity and stability of the lithium battery electrode being preheated by the two preheating rollers 301 to a certain extent.

[0054] In the specific implementation process, such as Figure 5 , Figure 8 , Figure 10 and Figure 13 As shown, two preheating rollers 301 are symmetrically arranged vertically. Guide rollers 302 located on both sides of the middle position of the two preheating rollers 301 are rotatably installed in the second base 3. The lithium battery electrode sheet is guided by the two preheating rollers 301 and the two guide rollers 302 to form an "8" shape. The ends of the two preheating rollers 301 are fixed with meshing gears 303. The upper preheating roller 301 is connected to the rear guide roller 302 by a first sprocket drive assembly 304, and the lower preheating roller 301 is connected to the front guide roller 302 by a second sprocket drive assembly 305.

[0055] When in use, the lithium battery electrode is wound around the bottom of the front guide roller 302, then upwards around the top of the upper preheating roller 301, then downwards around the bottom of the lower preheating roller 301, and finally upwards out from the top of the rear guide roller 302. Following the initial conveying trajectory, the lithium battery electrode, guided by the two preheating rollers 301 and the two guide rollers 302, forms an "8" shape on its side. The two guide rollers 302 are respectively positioned on the front and rear sides of the middle position of the upper and lower preheating rollers 301. This allows the lithium battery electrode to wrap around the preheating rollers 301 significantly when it passes over them, and makes the positions of the upper and lower preheating rollers 301 more concentrated. This not only effectively increases the contact area between the lithium battery electrode and the preheating rollers 301 during the conveying process, but also reduces the efficiency of heat dissipation by concentrating the heat source, which is beneficial to improving the effect of the lithium battery electrode being preheated by the heat on the preheating rollers 301.

[0056] During operation, one of the preheating rollers 301 is connected to a servo motor, which drives the preheating roller 301 to rotate. Taking the lower preheating roller 301 connected to the servo motor as an example, the rotation of the lower preheating roller 301 drives the lower gear 303 to rotate. Through the meshing of the two gears 303, the upper preheating roller 301 is driven to rotate in the opposite direction, connected by the first sprocket drive assembly 304. The rear guide roller 302 rotates in the same direction as the upper preheating roller 301, connected by the second sprocket drive assembly 305. The square guide roller 302 rotates in the same direction as the lower preheating roller 301, which conforms to the conveying trajectory of the lithium battery electrode under the guidance of the two preheating rollers 301 and the two guide rollers 302. This allows a single servo motor to drive the two preheating rollers 301 and the two guide rollers 302 to rotate synchronously and stably, which is beneficial to improving the ease of operation of the device. When the preheating rollers 301 and the guide rollers 302 rotate, the linear velocity of their outer surfaces is matched with the conveying speed of the lithium battery electrode, which helps to ensure the stability of the lithium battery electrode during the conveying under the guidance of the two preheating rollers 301 and the two guide rollers 302.

[0057] In the specific implementation process, such as Figure 2 , Figure 8 and Figure 13As shown, heat insulation covers 203 are fitted on the outer sides of both upper and lower pressure rollers 103. A heat insulation box 306 is fixed inside the second machine base 3, which is fitted on the outer sides of the two preheating rollers 301 and the two guide rollers 302. When the device is in use, heat insulation cotton is provided inside the end walls of the heat insulation covers 203 and the second machine base 3. The inner end walls of the heat insulation covers 203 and the second machine base 3 are made into smooth mirror surfaces. The heat insulation covers 203 can reduce the efficiency of heat dissipation from the pressure rollers 103 to the outside, and the heat insulation box 306 can reduce the efficiency of heat dissipation from the preheating rollers 301 to the outside. This helps to reduce the heat loss when the device hot rolls process lithium battery electrodes, and further improves the energy efficiency of the device.

[0058] In the specific implementation process, such as Figure 6 , Figure 8 and Figure 12 As shown, an air blowing box 5 located in front of the heat preservation box 306 is fixed on the second base 3. The lithium battery electrode is movably inserted in the middle position inside the air blowing box 5. The air blowing box 5 has longitudinally arranged airflow channels 501 fixed on the left and right sides, and the rear end of the airflow channel 501 is fixedly connected to the second adapter pipe 402. A number of symmetrically arranged guide plates 502 are fixed on the inner end walls of the upper and lower sides of the air blowing box 5. The guide plates 502 are inclined inside the air blowing box 5. One end of the guide plate 502 points to the front opening of the air blowing box 5, and the other end of the guide plate 502 extends into the airflow channel 501. The numerous guide plates 502 are evenly distributed from back to front, and the length of the part extending into the airflow channel 501 gradually increases.

[0059] When the device is in use, since the air blowing box 5 is located directly in front of the heat preservation box 306, the lithium battery electrode sheets will pass through the air blowing box 5 before being preheated by the preheating roller 301 inside the heat preservation box 306. During the lithium battery electrode sheet conveying process, the sheet enters through the front end of the air blowing box 5 and exits through the rear end. During this process, the airflow conveyed in the second transfer pipe 402 enters through the rear end of the airflow channel 501 and flows from back to front within the airflow channel 501. Then, with the guidance of numerous guide plates 502 evenly distributed from back to front, the airflow is evenly dispersed within the air blowing box 5 and flows from back to front. The airflow blows on both sides of the lithium battery electrode sheets in the air blowing box 5, which can clean the front and back sides of the lithium battery electrode sheets by air blowing. This can prevent impurities from adhering to the lithium battery electrode sheets during the hot rolling process, which would cause damage to the lithium battery electrode sheets after rolling. This improves the stability of the device during operation to a certain extent.

[0060] Meanwhile, since the second adapter pipe 402 draws out airflow through the preheating roller 301, although the temperature of the airflow blown out from the preheating roller 301 is further reduced to a certain extent, it is still higher than the initial temperature of the lithium battery electrode. By using the drawn-out airflow to blow air onto the lithium battery electrode in the air blowing box 5, not only can the lithium battery electrode be cleaned by air blowing, but the lithium battery electrode can also be preheated in front of the preheating roller 301. The air blowing box 5, the preheating roller 301 and the heat insulation cover 203 in the heat insulation box 201 cooperate with each other to realize a three-stage heating mode of double preheating and one direct heating. This makes the heating of the lithium battery electrode present as a step, which can effectively improve the heating uniformity of the lithium battery electrode and avoid damage caused by sudden temperature rise of the lithium battery electrode. This is conducive to further improving the stability of the device when hot rolling the lithium battery electrode.

[0061] In the specific implementation process, such as Figure 8 As shown, the top of the rear guide roller 302 is flush with the top of the lower pressure roller 103, and the bottom of the front guide roller 302 is flush with the inner center plane of the air blowing box 5. When the device is in use, the bottom of the front guide roller 302 is flush with the inner center plane of the air blowing box 5, which allows the lithium battery electrode to be smoothly and stably introduced from the air blowing box 5 into the front guide roller 302. Similarly, the top of the rear guide roller 302 is set to be flush with the top of the lower pressure roller 103, so that the lithium battery electrode can be horizontally introduced between the upper and lower pressure rollers 103 for roll forming. This ensures that the lithium battery electrode is tangent to the outer surface of the upper and lower pressure rollers 103, and can prevent the lithium battery electrode from being skewed when it is fed between the upper and lower pressure rollers 103. This improves the stability and accuracy of the device when hot roll forming lithium battery electrodes to a certain extent.

[0062] Specifically, the working principle and operation method of this invention are as follows:

[0063] The lithium battery electrode is heated in three stages. After the electric heating component 202 is powered on, it directly heats the bottom of the upper pressure roller 103 and the top of the lower pressure roller 103 under the cover of the heat insulation box 201, heating the bottom of the upper pressure roller 103 and the top of the lower pressure roller 103 to 140°C. Then the air pump is powered on and blows the airflow. The airflow enters from the air inlet pipe 4, passes through the heat insulation box 201 and is introduced into the preheating roller 301 through the first adapter pipe 401. During this process, the airflow is heated and introduced into the preheating roller 301, heating the preheating roller 301 to 80°C. The airflow in the preheating roller 301 is introduced into the airflow channel 501 through the second adapter pipe 402. It flows from back to front in the airflow channel 501 and is evenly dispersed into the air blowing box 5 with the help of many guide plates 502, heating the temperature in the air blowing box 5 to 40°C.

[0064] During the lithium battery electrode conveying process, the first stage of preheating is carried out. After passing through the air blowing box 5, the lithium battery electrode is heated to 40°C by the blowing of hot air. Simultaneously, the front and back of the lithium battery electrode are cleaned by air blowing. Then, the lithium battery electrode undergoes a second stage of preheating. The lithium battery electrode passes orderly around two preheating rollers 301 and two guide rollers 302. With the front and back of the lithium battery electrode in close contact with the two preheating rollers 301 in turn, the temperature of the lithium battery electrode is raised from 40°C to 80°C. Finally, the third stage of direct heating is carried out, and a rolling operation is performed simultaneously. The lithium battery electrode is inserted between the upper and lower pressure rollers 103. Through contact with the outer surfaces of the two pressure rollers 103, the temperature is rapidly raised from 80°C to 140°C. The relative rotation of the upper and lower pressure rollers 103 completes the hot rolling process of the lithium battery electrode.

[0065] The above are merely preferred embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A lithium battery electrode hot rolling device, comprising a first machine base (1), characterized in that: A vertically arranged electric lift (101) is installed on the first base (1), and a lifting platform (102) is fixed on the sliding end of the electric lift (101). A horizontally arranged pressure roller (103) is rotatably installed inside both the first base (1) and the lifting platform (102). The two pressure rollers (103) are symmetrically arranged vertically and rotate relative to each other. Lithium battery electrode sheets are inserted between the upper and lower pressure rollers (103). A crossbeam (2) is movably inserted at the central axis position inside each pressure roller (103). The crossbeam (2) of the square is fixedly connected to the first base (1), and the upper crossbeam (2) is fixedly connected to the lifting platform (102). A heat insulation box (201) is fixed on the crossbeam (2) and slides against the inner end wall of the pressure roller (103). The lower heat insulation box (201) faces the upper inner end wall of the lower pressure roller (103), and the upper heat insulation box (201) faces the lower inner end wall of the upper pressure roller (103). An electric heating component (202) is fixed inside the heat insulation box (201).

2. The lithium battery electrode hot rolling device according to claim 1, characterized in that: The pressure roller (103) has a first bevel tooth (104) fixed at its end. A vertically arranged spline shaft (105) is rotatably mounted inside the first machine base (1). A second bevel tooth (106) that meshes with the lower first bevel tooth (104) is fixed on the spline shaft (105). A spline cylinder (107) is slidably sleeved on the spline shaft (105). A third bevel tooth (108) that meshes with the upper first bevel tooth (104) is fixed on the spline cylinder (107).

3. The lithium battery electrode hot rolling device according to claim 1, characterized in that: A second base (3) is provided in front of the first base (1), and two preheating rollers (301) rotate inside the second base (3). The interior of the preheating rollers (301) is set as a hollow structure. The lithium battery electrode passes around the two preheating rollers (301) in sequence, and the front and back sides of the lithium-ion electrode are respectively attached to the outer surfaces of the two preheating rollers (301). Both ends of the crossbeam (2) are connected to the interior of the heat insulation box (201). One end of the crossbeam (2) is connected to the air inlet pipe (4), and the other end of the crossbeam (2) is connected to the first adapter pipe (401). The other end of the first adapter pipe (401) is rotatably connected to one end of the preheating roller (301), and the other end of the preheating roller (301) is rotatably connected to the second adapter pipe (402).

4. The lithium battery electrode hot rolling device according to claim 3, characterized in that: The two preheating rollers (301) are arranged symmetrically on top of each other. The second base (3) is rotatably installed with guide rollers (302) located on both sides of the middle position of the two preheating rollers (301). The lithium battery electrode sheet is guided by the two preheating rollers (301) and the two guide rollers (302) to form an "8" shaped structure.

5. The lithium battery electrode hot rolling device according to claim 4, characterized in that: The ends of the two preheating rollers (301) are fixed with meshing gears (303). The upper preheating roller (301) is connected to the rear guide roller (302) by a first sprocket drive assembly (304), and the lower preheating roller (301) is connected to the front guide roller (302) by a second sprocket drive assembly (305).

6. The lithium battery electrode hot rolling device according to claim 4, characterized in that: The outer sides of the upper and lower pressure rollers (103) are covered with heat insulation covers (203), and the second machine base (3) is fixed with a heat insulation box (306) that is covered with the outer sides of the two preheating rollers (301) and the two guide rollers (302).

7. The lithium battery electrode hot rolling device according to claim 6, characterized in that: The second base (3) is fixed with an air blowing box (5) located in front of the heat preservation box (306). The lithium battery electrode is movably inserted in the middle position inside the air blowing box (5). The air blowing box (5) is fixed with longitudinally arranged airflow channels (501) on the left and right sides, and the rear end of the airflow channel (501) is fixedly connected to the second adapter pipe (402).

8. The lithium battery electrode hot rolling device according to claim 7, characterized in that: Numerous symmetrically arranged guide plates (502) are fixed on the inner walls of the upper and lower sides of the air blowing box (5). The guide plates (502) are inclined inside the air blowing box (5). One end of the guide plate (502) points to the front opening of the air blowing box (5), and the other end of the guide plate (502) extends into the airflow channel (501). The numerous guide plates (502) are evenly distributed from back to front, and the length of the part extending into the airflow channel (501) gradually increases.

9. A lithium battery electrode hot rolling device according to claim 7, characterized in that: The top of the rear guide roller (302) is flush with the top of the lower pressure roller (103), and the bottom of the front guide roller (302) is flush with the center plane inside the air blowing box (5).

10. A method for rolling lithium battery electrodes, characterized in that, The rolling method uses the lithium battery electrode hot rolling device as described in any one of claims 1-9, and the rolling method includes the following steps: S1. Preheating: Hot air enters from the rear end of the airflow channel (501) through the second adapter pipe (402), flows from back to front in the airflow channel (501), and is evenly dispersed in the air blowing box (5) under the guidance of numerous guide plates (502) to preheat the lithium battery electrode sheets passing through the air blowing box (5) and simultaneously clean the front and back sides of the lithium battery electrode sheets with air blowing. The lithium battery electrode sheets are heated to 40°C after passing through the air blowing box (5). S2. Second-stage preheating: During the transport of lithium battery electrode sheets, the two preheating rollers (301) and two guide rollers (302) are orderly bypassed. Simultaneously, hot air enters the preheating roller (301) through the first transfer pipe (401) and heats the preheating roller (301) to 80°C. The two preheating rollers (301) are then tightly bonded to the front and back sides of the lithium battery electrode sheet in sequence, raising the temperature of the lithium battery electrode sheet after the first stage of preheating from 40°C to 80°C. S3. Three-stage direct heating: The electric heating component (202) inside the heat insulation box (201) is powered on and started, heating the bottom of the upper pressure roller (103) and the top of the lower pressure roller (103) to 140°C. The lithium battery electrode sheet, which has been preheated in two stages, is conveyed between the upper and lower pressure rollers (103). Through the contact between the lithium battery electrode sheet and the similar outer surfaces of the upper and lower pressure rollers (103), the temperature of the lithium battery electrode sheet is rapidly increased from 80°C to 140°C. S4. Rolling: The lithium battery electrode sheet heated to 140°C is placed between two upper and lower pressure rollers (103). The distance between the two upper and lower pressure rollers (103) is adjusted by an electric lifting machine (101). With the relative rotation of the two upper and lower pressure rollers (103), the rolling process is completed during the lithium battery electrode sheet conveying process.

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