Pole piece coating device and pole piece coating method

Abstract

The application provides an electrode sheet coating device and an electrode sheet coating method. The electrode sheet coating device comprises: a marking mechanism for spraying marks on one side of a substrate; a coating mechanism for coating slurry on both sides of the substrate with the marks staggered; a first measurer for acquiring position information of the marks and detecting a first area density of the substrate corresponding to the position of the marks; a second measurer for acquiring position information of the marks and detecting a second area density of the substrate and the slurry corresponding to the position of the marks; and a controller for acquiring a coating weight of the slurry according to the first area density and the second area density and adjusting a coating amount of the coating mechanism according to the coating weight. The coating weight of the slurry corresponding to the same mark position is acquired by the first measurer and the second measurer, so that the coating weight of the slurry of the front and rear parts in the feeding direction of the substrate is consistent, thereby ensuring the consistency of the weight of the electrode sheet.

Description

Technical Field

[0001] The present invention relates to the technical field of pole piece coating, and in particular to a pole piece coating device and a pole piece coating method. Background Art

[0002] One of the steps in the battery production process is to apply the positive and negative electrode slurry to the surface of the current collector to form the positive and negative electrode sheets, which are the components of the battery cell.

[0003] During the coating process, a measuring instrument is typically used to scan and measure the weight of the coated substrate and both coated surfaces in real time to ensure that the weight of the coated electrode is within process requirements. However, existing measuring instruments lack an effective solution for measurement consistency, resulting in variations in electrode weight within the battery cell, which can affect battery performance. Summary of the Invention

[0004] The embodiments of the present application provide a pole piece coating device and a pole piece coating method to improve the consistency of pole piece coating and reduce the impact of pole piece weight differences on battery performance.

[0005] The present invention provides a pole piece coating device, comprising:

[0006] a substrate having two opposing sides for coating;

[0007] a marking mechanism, for spraying a mark onto one side of the substrate;

[0008] A coating mechanism, located after the marking mechanism in the feeding direction, and configured to apply slurry to the two side surfaces of the substrate while staggering the markings;

[0009] a first measuring device, disposed between the coating mechanism and the marking mechanism, the first measuring device being used to obtain position information of the mark and detect a first surface density of the substrate corresponding to the mark position;

[0010] a second measuring device, disposed after the coating mechanism in the feeding direction, for obtaining position information of the mark and detecting a second surface density of the substrate and the slurry corresponding to the mark position;

[0011] A controller is electrically connected to the first measuring device, the second measuring device and the coating mechanism, and is used to obtain the coating weight of the slurry according to the first surface density and the second surface density, and adjust the coating amount of the coating mechanism according to the coating weight.

[0012] The present application also provides a method for coating a pole piece, comprising:

[0013] Spraying a mark onto one side of the substrate;

[0014] Acquiring position information of the mark, and detecting a first surface density of the substrate corresponding to the mark position;

[0015] staggering the marks and applying the slurry to the substrate;

[0016] Acquiring position information of the mark, and detecting a second surface density of the substrate and the slurry corresponding to the mark position;

[0017] The coating weight of the slurry is obtained according to the first areal density and the second areal density, and the coating amount of the coating slurry is adjusted according to the coating weight.

[0018] In the electrode coating device and electrode coating method provided in the embodiments of the present application, a marking mechanism is set to spray mark the substrate, and the coating weight of the slurry corresponding to the same marking position is obtained according to the first measuring instrument and the second measuring instrument. This is used as the basis for adjusting the coating amount of the coating mechanism, so that the slurry coating weight of the front and rear parts of the substrate in the feeding direction can be consistent, thereby ensuring the consistency of the electrode weight and reducing the impact of the electrode weight difference on the battery performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] To more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present application. Those skilled in the art can also derive other drawings based on these drawings without inventive effort.

[0020] Figure 1 This is a schematic diagram of the structure of the electrode coating device provided in an embodiment of the present application.

[0021] Figure 2 A schematic diagram of a partial structure of a substrate and electrode coating device provided in an embodiment of the present application.

[0022] Figure 3 for Figure 1 The schematic diagram of the structure of part of the electrode coating device is shown.

[0023] Figure 4 A schematic flow chart of the electrode coating method provided in an embodiment of the present application.

[0024] Description of Reference Numerals

[0025] 10-substrate 11-material strip 12-mark

[0026] 13- Setting area 2- Pole coating device 20- Marking mechanism

[0027] 21- coating mechanism 22- first measuring device 220- identification device

[0028] 221- Scanner 23- Second Measuring Device 24- Controller

[0029] 25- Drying mechanism 26- Third measuring device 30- Base

[0030] 31-Second bracket 32-Third bracket 33-Fourth bracket

[0031] X-feed direction Y-first direction. DETAILED DESCRIPTION

[0032] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the embodiments described are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without making creative efforts are within the scope of protection of this application.

[0033] See also Figure 1 , Figure 1 A schematic structural diagram of a pole piece coating device provided in an embodiment of the present application. An embodiment of the present application provides a pole piece coating device 2, which is used in the production process of battery pole pieces. One of the steps in the battery production process is to coat the positive and negative electrode slurries on the surface of the current collector, and obtain the positive and negative pole pieces after drying and cutting. The positive and negative pole pieces are the main components of the battery cells, and the battery cells are encapsulated in a shell to form a battery. Among them, during the coating process, a measuring instrument is usually used to scan and measure the coating substrate and the weight of the coated single and double sides in real time to ensure that the weight of the coated pole piece is within the process requirements. However, the existing measuring instruments have not found an effective way to solve the problem of measurement consistency, which leads to differences in the weight of the pole pieces in the battery cells and affects the performance of the battery.

[0034] The embodiment of the present application improves the electrode coating device 2 to adjust the uniformity of the slurry coating, thereby making the electrode weight consistent and improving the performance of the battery.

[0035] Exemplarily, the electrode coating device 2 includes a substrate 10 , a marking mechanism 20 , a coating mechanism 21 , a first measuring device 22 , a second measuring device 23 and a controller 24 .

[0036] Please combine Figure 1 See also Figure 2 , Figure 2Schematic diagram of a scene of part of the structure of the substrate and electrode coating device provided in the embodiment of the present application. The substrate 10 is the basic structure for slurry coating. The substrate corresponding to the electrode of each battery can also be called a current collector. The current collector is a structure or part that collects current. In the electrode production process, in order to improve production efficiency, the substrate 10 is usually arranged and rolled up, and the substrate 10 is continuously unwound for coating. The substrate 10 and the slurry dry film after coating and drying are used as the electrode strip 11. The strip is cut to obtain batches of electrodes, thereby carrying out large-scale production of electrodes. The substrate 10 has two opposite side surfaces for coating, wherein, for each side of the substrate 10, it can be coated with slurry in multiple areas along a first direction Y perpendicular to the feed direction X. Thus, multiple strips 11 can be obtained at the same time, thereby improving production efficiency. The areas of the multiple substrates 10 coated with slurry can be spaced in sequence to leave a margin for cutting or to prevent interference.

[0037] The marking mechanism 20 is used to spray a mark 12 onto one side of the substrate 10. For example, the marking mechanism 20 can be a mechanism with a spray terminal and a liquid supply component, which provides coding liquid through the liquid supply component, and the spray terminal sprays liquid toward the target to form a mark 12. By setting the spray shape of the spray terminal, marks 12 of different sizes and shapes can be formed. For example, in the embodiment of the present application, a mark 12 can be sprayed on one side of the substrate 10, and the mark 12 can be a square pattern with a side length of 10 mm. In order to prevent the mark 12 from being covered by the slurry, the mark 12 can be sprayed on a blank area outside the material strip 11 formed on the substrate 10, such as in the first direction Y, spraying the mark 12 on the upper end of one side of the substrate 10. Of course, the spraying position of the mark 12 is not limited, and any position on the substrate 10 that is not blocked by the slurry can be used.

[0038] The coating mechanism 21 is used to apply slurry to both sides of the substrate 10. The coating mechanism 21 may also have a slurry supply component and a nozzle, and the number of nozzles can be set as needed, such as Figure 2As described in, three nozzles can be set to spray the substrate 10, and the spraying area of ​​each nozzle is adaptively designed according to the size of the electrode. By adjusting the spraying amount of the slurry coated by the nozzle, slurries of different weights and slurry dry films can be formed. The electrode coating device 2 can be provided with a workbench or a base, and the coating mechanism 21 can be fixed relative to the workbench or the base, and the slurry is coated on different areas of the substrate 10 by unwinding and feeding the substrate 10. Exemplarily, in the feeding direction X, the coating mechanism 21 is located after the marking mechanism 20. The coating mechanism 21 is used to stagger the mark 12 to coat the slurry on both sides of the substrate 10. It should be noted that for the coating of the slurry on both sides of the substrate 10, one coating mechanism 21 can be used. For example, after the coating of one side of the substrate 10 is completed, the substrate 10 is turned over to use the same coating mechanism 21 to coat the other side of the substrate 10. Two or more coating mechanisms 21 can also be used to coat both sides of the substrate 10. The two coating mechanisms 21 can be set on opposite sides of the substrate 10, or the relative positions of the two sides of the substrate 10 and the two coating mechanisms 21 can be changed by winding the substrate 10.

[0039] The first measuring device 22 is positioned between the coating mechanism 21 and the marking mechanism 20. The first measuring device 22 is used to obtain the positional information of the marking 12 and detect the first areal density of the substrate 10 at the position corresponding to the marking 12. In the feed direction X, the second measuring device 23 is positioned after the coating mechanism 21. The second measuring device 23 is used to obtain the positional information of the marking 12 and detect the second areal density of the substrate 10 and the slurry at the position corresponding to the marking 12.

[0040] The controller 24 is electrically connected to the first measuring device 22, the second measuring device 23 and the coating mechanism 21. The controller 24 is used to obtain the coating weight of the slurry according to the first surface density and the second surface density, and adjust the coating amount of the coating mechanism 21 according to the coating weight. The controller 24 can be understood as the control center of the electrode coating device 2. The controller 24 can control the timing of the first measuring device 22 to collect the position information of the mark 12, and the timing of detecting the first surface density of the position of the mark 12 of the substrate 10. The control of the second measuring device 23 by the controller 24 can refer to the first measuring device 22 and will not be repeated here. The controller 24 can also be electrically connected to the marking mechanism 20 to control the timing of the marking spraying by the marking mechanism 20, the position of the spraying mark, etc. The controller 24 can also control the coating amount of the coating mechanism 21. For example, the controller 24 can be controlled by a PLC (Programmable Logic Controller). A PLC control system is a new generation of industrial control devices that incorporates microelectronics, computer technology, automatic control technology, and communication technology based on traditional sequential controllers. Its purpose is to replace relays, execution logic, timing, counting, and other sequential control functions, and establish a flexible remote control system. It has the characteristics of high versatility, ease of use, wide adaptability, high reliability, strong anti-interference ability, and simple programming.

[0041] In the electrode coating device 2 provided in the embodiment of the present application, a marking mechanism 20 is provided to spray a mark 12 on the substrate 10, and the coating weight of the slurry corresponding to the same marking position is obtained according to the first measuring device 22 and the second measuring device 23. This is used as the basis for adjusting the coating amount of the coating mechanism 21, so that the coating weight of the slurry in the front and rear parts of the substrate 10 in the feed direction X can be consistent, thereby ensuring the consistency of the electrode weight and reducing the impact of the electrode weight difference on the battery performance.

[0042] For example, please see Figure 1 and Figure 2 The first measuring device 22 and the second measuring device 23 both include an identifier 220 and a scanner 221 , and the identifier 220 is electrically connected to the scanner 221 .

[0043] The identifier 220 is used to obtain the position information of the mark 12. For example, the identifier 220 may be a color mark sensor, which is commonly used to detect specific color marks or spots on an object. It detects the color mark by comparing it with non-color mark areas, rather than directly measuring the color. A color mark sensor is actually an inverted device. The light source is mounted perpendicular to the target object, while the receiver is mounted at an acute angle to the object. This allows it to detect only scattered light from the target object, preventing the sensor from directly receiving reflected light and allowing for a very narrow light beam focus. Both incandescent lamps and monochromatic light sources can be used for color mark detection. The color mark sensor can identify the pattern of the mark 12 and its position information. For another example, the identifier 220 may be a camera or camcorder, which captures an image and compares it with a preset mark to obtain the mark 12 and its position information. Of course, the identifier 220 can also be an instrument of other types or based on other principles, and these examples are not given here.

[0044] The scanner 221 can scan the set area 13 according to the position information of the mark 12 to obtain the first surface density of the substrate 10 corresponding to the set area 13 or the second surface density of the substrate 10 and the slurry corresponding to the set area 13. It should be noted that the mass of the electrode per unit area is called the surface density of the electrode. The surface density of the electrode is the most important factor in determining the consistency of the battery. The scanner 221 can be a surface density weighing instrument. The working principle of the surface density weighing instrument is: when the beta rays generated by the decay of Kr85 (krypton 85) penetrate the battery electrode, a portion of the rays are absorbed by the electrode. As a result, the intensity of the rays after penetrating the electrode is attenuated relative to the intensity of the incident rays. The attenuation ratio is inversely proportional to the surface density of the penetrated electrode. By detecting the intensity of the rays before and after penetrating the electrode in an ionization chamber filled with a special gas, the surface density of the electrode can be calculated. The surface density is defined as the mass m of the electrode per unit area s. The scanner 221 can directly obtain the surface density of the set area 13, thereby obtaining the coating weight of the slurry in the set area 13. By scanning the same set area 13 with the first measuring instrument 22 and the second measuring instrument 23, the surface density of the slurry in the same set area 13 can be obtained, which serves as the basis for adjusting the coating amount of the coating mechanism 21, thereby ensuring the consistency of the electrode weight.

[0045] Among them, the scanner 221 can move along a first direction Y perpendicular to the feeding direction X, so that the set area 13 can be scanned and detected. For example, when it is necessary to scan the set area 13, the substrate 10 can be stopped from feeding, and the scanner 221 can control the feeding of the substrate 10 after the scanning of the set area 13 is completed. Of course, the scanner 221 can also be controlled to scan and detect the set area 13 by matching the movement trajectory of the scanner 221 with the feeding speed of the substrate 10. The movement of the scanner 221 can be achieved by setting a bracket structure. For example, a first bracket extending along the first direction Y can be set on the base of the electrode coating device 2, and the scanner 221 is slidably connected to the first bracket along the first direction Y. The identifier 220 is slidably connected to the scanner 221 along the feeding direction X, so that the identifier 220 can follow the scanner 221 to move along the first direction Y, and the identifier 220 can also move relative to the scanner 221 along the feeding direction X to achieve recognition and acquisition of the mark 12.

[0046] For example, see Figure 3 , Figure 3 for Figure 1 A schematic diagram of a portion of the electrode coating apparatus is shown. The identifier 220 can move within a predetermined region of the substrate 10 along a first direction Y and a feed direction X. For example, the identifier 220 can be slidably connected to the second bracket 31 along the feed direction X, and the second bracket 31 can be slidably connected to the base 30 along the first direction Y.

[0047] The marking mechanism 20 can also be moved to a preset position for spraying the mark. For example, the marking mechanism 20 can be slidably installed on the third bracket 32 ​​along the feed direction X, so as to realize the movement of the marking mechanism 20 along the feed direction X. The third bracket 32 ​​is slidably connected to the fourth bracket 33 in the direction of approaching or moving away from the substrate 10. The third bracket 32 ​​can move closer to the substrate 10 or move away from the substrate 10 relative to the fourth bracket 33, and drive the marking mechanism 20 closer to or away from the substrate 10. The fourth bracket 33 can be slidably connected to the base 30 along the first direction Y to drive the marking mechanism 20 to move along the first direction Y. Since the marking mechanism 20 can move closer to or away from the substrate 10, the movement of the identifier 220 can be avoided to prevent interference between the two. Of course, the relative position of the marking mechanism 20 and the identifier 220 is Figure 3 It is just a schematic diagram to show that the movement of the identification device 220 and the movement of the marking mechanism 20 can be achieved through the setting of the brackets and the connection between the brackets, and should not be understood as a restriction on the actual positional relationship between the marking mechanism 20 and the identification device 220.

[0048] For example, the first measuring device 22 can be communicatively connected to the second measuring device 23 to adjust the scanning position of the scanner 221 of the second measuring device 23, thereby improving the measurement accuracy of the first and second measuring devices 22, 23 with respect to the designated area 13. For example, the identifier 220 of the first measuring device 22 is used to obtain first position information of the mark 12, while the identifier 220 of the second measuring device 23 is used to obtain second position information of the mark 12. During the feeding process of the substrate 10, the roller may fail to flatten the substrate 10. Flattening can be understood as keeping the substrate 10 within a preset position range in both the first direction Y and the feeding direction X. As a result, the first position information obtained by the first measuring device 22 and the second position information obtained by the second measuring device 23 may not match, resulting in the second measuring device 23 scanning different designated areas 13 than the first measuring device 22. To address this issue, embodiments of the present application also provide for deviation correction of the scanning position of the second measuring device 23. Exemplarily, the controller 24 is electrically connected to the identifier 220 of the first measuring device 22 and the identifier 220 of the second measuring device 23, respectively. The controller 24 is used to obtain a position error based on the first position information and the second position information, and adjust the scanning position of the scanner 221 of the second measuring device 23 based on the position error so that the scanner 221 of the second measuring device 23 can scan the set area 13, so that the first measuring device 22 and the second measuring device 23 scan the surface density of the same area, thereby ensuring the detection accuracy of the slurry coating weight. Of course, the first position information and the second position information can also be used as the basis for correcting the substrate 10. After the substrate 10 is straightened, the second measuring device 23 scans the set area 13 again. The communication connection between the first measuring device 22 and the second measuring device 23 can realize the correction of the scanning set area 13, thereby ensuring the detection accuracy of the slurry coating weight. In addition, the communication connection between the first measuring device 22 and the second measuring device 23 can also serve as the basis for correcting the substrate 10. The reuse of the first measuring device 22 and the second measuring device 23 can save components and reduce the cost of the electrode coating device 2.

[0049] It should be noted that the second measuring device 23 can detect the second areal density of the substrate 10 and the slurry in the wet state, and then the wet slurry coating weight can be obtained based on the first areal density of the substrate 10 obtained by the first measuring device 22. Since the weight of the slurry in the dry film state is the coating weight of the formed electrode, the weight of the dry film slurry can also be used as the basis for adjusting the coating amount of the coating mechanism 21.

[0050] Exemplarily, the electrode coating device 2 further includes a drying mechanism 25 and a third measuring device 26 .

[0051] In the feeding direction X, a drying mechanism 25 is disposed after the second measuring device 23. The drying mechanism 25 is used to dry the coating slurry to obtain a dry film. The drying mechanism 25 is a mechanism that dries the coated slurry by heating. The drying mechanism 25 can be performed by blowing hot air onto the coated slurry, or by radiating heat to the coated slurry through a heat-conducting structure.

[0052] In the feeding direction X, the third measuring device 26 is arranged after the drying mechanism 25. The third measuring device 26 is used to obtain the position information of the mark 12 and detect the third surface density of the substrate 10 and the dry film corresponding to the position of the mark 12. For example, the third surface density of the set area 13 can be detected. The third surface density is compared with the first surface density to obtain the weight of the dry film, and the weight of the dry film is used as the basis for adjusting the coating amount of the coating mechanism 21. Alternatively, the third surface density is compared with the second surface density to obtain the weight difference between the dry film and the wet film, which is used to confirm the accuracy of the coating amount of the coating mechanism 21 previously adjusted according to the second surface density and the first surface density. Among them, the controller 24 is electrically connected to the third measuring device 26, and the controller 24 is also used to adjust the coating amount of the coating mechanism 21 according to the third surface density. The structural composition of the third measuring device 26 can refer to the description of the first measuring device 22 and the second measuring device 23. The difference is that the third measuring device 26 is set at a different position from the first measuring device 22 and the second measuring device 23.

[0053] In order to realize the coating, drying and inspection of the slurry on the two opposite sides of the substrate 10, the electrode coating device 2 may include two second measuring devices 23, two third measuring devices 26, two coating mechanisms 21 and two drying mechanisms 25. The two second measuring devices 23 are electrically connected to the controller 24, and the controller 24 is used to obtain the two coating weights of the slurry on the two sides of the substrate 10, and adjust the coating amount of the coating mechanism 21 according to each coating weight. The two third measuring devices 26 are electrically connected to the controller 24, and the controller 24 is used to obtain the two coating weights of the dry film on the two sides of the substrate 10, and adjust the coating amount of the coating mechanism 21 according to each coating weight. The two coating mechanisms 21 coat the two sides of the substrate 10 respectively. The two drying mechanisms 25 dry the coating slurry on the two sides of the substrate 10 respectively.

[0054] For example, in the feed direction X, a marking mechanism 20, a first measuring device 22, a coating mechanism 21, a second measuring device 23, a drying mechanism 25, and a third measuring device 26 are arranged in sequence. The substrate 10 is flipped by a roller structure. Another coating mechanism 21, another second measuring device 23, another drying mechanism 25, and another third measuring device 26 are arranged in sequence in the feed direction X. Finally, the coated substrate 10 is rolled up. The electrode coating device 2 configured in this way has a compact structure, eliminates the need to manually flip the substrate 10, reduces the occurrence of position deviation of the substrate 10, and can improve the coating effect and coating uniformity of the electrode.

[0055] like Figure 4 As shown, Figure 4 This is a flow chart of the electrode coating method provided in the embodiment of the present application. The embodiment of the present application also provides a electrode coating method, which is applied to the above-mentioned electrode coating device 2. The electrode coating device 2 can refer to Figures 1 to 3 As well as the above description. The electrode coating method includes:

[0056] 101. Spray a mark onto one side of the substrate.

[0057] For example, a marking mechanism 20 can be used to spray a marking 12 onto one side of a substrate 10. For example, the marking mechanism 20 can be controlled to move to a predetermined area corresponding to the substrate 10, then controlled to move closer to the substrate 10, and then controlled to spray. By setting parameters such as the spraying speed and spraying amount of the marking mechanism 20, a marking 12 with a color and / or pattern can be sprayed onto a predetermined area of ​​the substrate 10. The spraying timing of the marking mechanism 20 can also be controlled, such as spraying when the substrate 10 stops feeding.

[0058] For example, the mark 12 may be sprayed on the upper end region of the substrate 10 along the first direction Y. The mark 12 may be a square pattern with a side length of 10 mm.

[0059] 102. Obtain position information of the mark, and detect a first surface density of the substrate corresponding to the mark position.

[0060] The position information of the mark 12 can be used as a reference for measuring the first surface density of the substrate 10. The mark 12 is set, and the weight of the coating slurry corresponding to the same mark position is detected as a reference for adjusting the subsequent coating amount.

[0061] For example, the position information of the mark 12 may be acquired first, and then the set area 13 may be scanned according to the position information of the mark 12 , thereby acquiring the first surface density of the substrate 10 in the set area 13 .

[0062] The above-described actions or steps can be performed by a first measuring device 22. The first measuring device 22 includes an identifier 220 and a scanner 221, with the identifier 220 electrically connected to the scanner 221. The identifier 220 is used to obtain positional information of the mark 12. For example, the identifier 220 can be moved to a position corresponding to the mark 12 to identify and detect the mark 12. The scanner 221 can scan a set area 13 based on the positional information of the mark 12 to obtain a first areal density of the substrate 10 corresponding to the set area 13. After obtaining the positional information of the mark 12, the scanner 221 is controlled to scan the set area 13 to obtain the first areal density of the substrate 10 in the set area 13.

[0063] 103. Apply the slurry to the substrate at staggered markings.

[0064] To prevent the mark 12 from being covered, the position of the mark 12 can be staggered when applying the slurry to the substrate 10. For example, a blank area and a coating area can be provided on the substrate 10. The mark 12 is sprayed on the blank area, and the slurry is applied to the substrate 10 in the coating area to prevent the slurry from covering the mark 12.

[0065] The coating mechanism 21 can be used to coat the substrate 10. The coating mechanism 21 is controlled to coat the coating area. Coating can be performed by moving the coating mechanism 21 or by providing multiple nozzles. By adjusting the amount of coating slurry sprayed, slurries of varying weights and dry slurry films can be formed. The weight of the coating slurry can be monitored and the amount of slurry applied adjusted to ensure uniform coating in the feed direction X, thereby improving the consistency of electrode weight.

[0066] 104. Obtain position information of the mark, and detect a second surface density of the substrate and the slurry corresponding to the mark position.

[0067] The position information of the mark 12 is obtained, and the set area 13 is scanned according to the position information of the mark 12 to obtain the second surface density of the substrate 10 and the slurry in the set area 13. The coating weight of the slurry is obtained by scanning the same area, which serves as the basis for adjusting the coating amount of the coating mechanism 21, thereby improving the uniformity of the electrode coating. The second measuring device 23 can be used to obtain the position information of the mark 12 and scan the set area 13. The second measuring device 23 includes an identifier 220 and a scanner 221, and the identifier 220 is electrically connected to the scanner 221. The identifier 220 is used to obtain the position information of the mark 12. For example, the identifier 220 can be moved to the position corresponding to the mark 12 to identify and detect the mark 12. The scanner 221 can scan the set area 13 according to the position information of the mark 12 to obtain the second surface density of the substrate 10 and the slurry in the set area 13. After obtaining the position information of the mark 12, the scanner 221 is controlled to scan the set area 13 to obtain the second surface density of the substrate 10 and the slurry in the set area 13.

[0068] Among them, during the feeding process of the substrate 10, the roller may not be able to flatten the substrate 10. Flattening can be understood as making the substrate 10 within the preset position range in both the first direction Y and the feeding direction X. As a result, the first position information obtained by the first measuring device 22 and the second position information obtained by the second measuring device 23 do not match, resulting in the second measuring device 23 and the first measuring device 22 scanning different set areas 13.

[0069] Exemplarily, the first position information and the second position information of the marker 12 may be obtained, a position error may be obtained based on the first position information and the second position information, and the scanning position may be adjusted based on the position error to scan the set area 13 .

[0070] For example, the scanning position of the second measuring device 23 can be corrected. The position error is obtained based on the first position information and the second position information, and the scanning position of the scanner 221 of the second measuring device 23 is adjusted according to the position error to scan the set area 13, so that the first measuring device 22 and the second measuring device 23 scan the surface density of the same area, thereby ensuring the detection accuracy of the slurry coating weight. Of course, the first position information and the second position information can also be used as the basis for correcting the substrate 10. After the substrate 10 is straightened, the second measuring device 23 scans the set area 13 again. The communication connection between the first measuring device 22 and the second measuring device 23 can realize the correction of the scanning set area 13, thereby ensuring the detection accuracy of the slurry coating weight. In addition, the communication connection between the first measuring device 22 and the second measuring device 23 can also serve as the basis for correcting the substrate 10. The reuse of the first measuring device 22 and the second measuring device 23 can save devices and reduce the cost of the electrode coating device 2.

[0071] 105. Obtain a coating weight of the slurry according to the first areal density and the second areal density, and adjust a coating amount of the coating slurry according to the coating weight.

[0072] Since the first surface density and the second surface density are both surface densities within the set area 13, the first surface density is the surface density of the substrate 10, and the second surface density is the surface density of the substrate 10 and the slurry. The difference between the second surface density and the first surface density is the weight of the wet coating slurry. According to this coating weight, the coating amount of the subsequent coating slurry can be adjusted to improve the uniformity of the slurry coating in the feed direction X, so that the weight of the electrode remains consistent.

[0073] In the electrode coating method provided in the embodiment of the present application, by spraying the mark 12 on the substrate 10, and then obtaining the coating weight of the slurry corresponding to the same mark position, which is used as the basis for adjusting the slurry coating amount, the slurry coating weight of the front and rear parts of the substrate 10 in the feed direction X can be made consistent, thereby ensuring the consistency of the electrode weight and reducing the impact of the electrode weight difference on the battery performance.

[0074] The second measuring device 23 can detect the second areal density of the substrate 10 and the slurry in the wet state, and the wet slurry coating weight can be obtained based on the first areal density of the substrate 10 obtained by the first measuring device 22. Since the weight of the slurry in the dry film state is the coating weight of the formed electrode, the dry film weight of the slurry can also be used as the basis for adjusting the coating amount of the coating mechanism 21.

[0075] For example, the applied slurry can be dried to obtain a dry film. The position information of the mark 12 is obtained, and the third surface density of the substrate 10 and the dry film corresponding to the marked position is detected. The coating amount of the coating slurry is adjusted according to the third surface density. For example, the third surface density of the set area 13 can be detected, and the third surface density can be compared with the first surface density to obtain the weight of the dry film, and the weight of the dry film is used as the basis for adjusting the coating amount of the coating mechanism 21. Alternatively, the third surface density can be compared with the second surface density to obtain the weight difference between the dry film and the wet film, which can be used to confirm the accuracy of the coating amount previously adjusted by the coating mechanism 21 based on the second surface density and the first surface density.

[0076] For example, the above-mentioned inspection steps may be performed on both opposite sides of the substrate 10 to improve the uniformity of the slurry coating on both sides of the substrate 10 , thereby improving the weight consistency of the electrode.

[0077] The above is a detailed introduction to the electrode coating device and electrode coating method provided in the embodiments of the present application. Specific examples are used herein to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the present application. At the same time, for those skilled in the art, based on the ideas of the present application, there will be changes in the specific implementation methods and application scope. In summary, the contents of this specification should not be understood as limiting the present application.

Claims

1. A pole piece coating device, characterized in that: include: a substrate having two opposing sides for coating; a marking mechanism, for spraying a mark onto one side of the substrate; a coating mechanism, located after the marking mechanism in the feeding direction, and configured to apply slurry to the two side surfaces of the substrate while staggering the markings; a first measuring device, disposed between the coating mechanism and the marking mechanism, the first measuring device being used to obtain position information of the mark and detect a first surface density of the substrate corresponding to the mark position; a second measuring device, disposed after the coating mechanism in the feeding direction, for obtaining position information of the mark and detecting a second surface density of the substrate and the slurry corresponding to the mark position; The first measuring device and the second measuring device both include: an identifier for obtaining position information of the marker; a scanner electrically connected to the recognition device, the scanner being capable of scanning a set area according to the position information of the mark to obtain a first surface density of the substrate corresponding to the set area or a second surface density of the substrate and the slurry corresponding to the set area; A controller is electrically connected to the first measuring device, the second measuring device and the coating mechanism, and is used to obtain the coating weight of the slurry at the same marked position based on the first surface density and the second surface density, and adjust the coating amount of the coating mechanism according to the coating weight.

2. The electrode coating device according to claim 1, characterized in that: The scanner is movable along a first direction perpendicular to the feeding direction; The identification device is slidably connected to the scanner along the feeding direction.

3. The electrode coating device according to claim 1, characterized in that: The identification device of the first measuring device is used to obtain the first position information of the mark; the identification device of the second measuring device is used to obtain the second position information of the mark; The controller is electrically connected to the identification instrument of the first measuring instrument and the identification instrument of the second measuring instrument respectively. The controller is used to obtain a position error based on the first position information and the second position information, and adjust the scanning position of the scanner of the second measuring instrument according to the position error so that the scanner of the second measuring instrument scans the set area.

4. The electrode coating device according to any one of claims 1 to 3, characterized in that: The pole piece coating device also includes: a drying mechanism, disposed after the second measuring device in the feeding direction, for drying the applied slurry to obtain a dry film; and a third measuring device, disposed after the drying mechanism in the feeding direction, for obtaining position information of the mark and detecting a third surface density of the substrate and the dry film corresponding to the mark position; The controller is electrically connected to the third measuring device, and is further configured to adjust the coating amount of the coating mechanism according to the third surface density.

5. The electrode coating device according to any one of claims 1 to 3, characterized in that: The electrode coating device includes two second measuring devices, which are electrically connected to the controller. The controller is also used to obtain two coating weights of the slurry on the two sides of the substrate and adjust the coating amount of the coating mechanism according to each coating weight.

6. A pole piece coating method, characterized in that: include: Spraying a mark onto one side of the substrate; Acquiring position information of the mark, and detecting a first surface density of the substrate corresponding to the mark position; staggering the marks and applying the slurry to the substrate; Acquiring position information of the mark, and detecting a second surface density of the substrate and the slurry corresponding to the mark position; The coating weight of the slurry is obtained according to the first areal density and the second areal density, and the coating amount of the coating slurry is adjusted according to the coating weight.

7. The electrode coating method according to claim 6, characterized in that: The obtaining of the position information of the mark and detecting the first surface density of the substrate corresponding to the position of the mark includes: Obtaining position information of the marker; Scanning a set area according to the position information of the mark to obtain a first surface density of the substrate in the set area; The obtaining of the position information of the mark and detecting the second surface density of the substrate and the slurry corresponding to the mark position includes: The set area is scanned according to the position information of the mark to obtain the second surface density of the substrate and the slurry in the set area.

8. The electrode coating method according to claim 7, characterized in that: Scanning the set area according to the position information of the mark to obtain the second surface density of the substrate and the slurry in the set area includes: Acquire first position information and second position information of the mark; Acquire a position error according to the first position information and the second position information; The scanning position is adjusted according to the position error to scan the set area.

9. The electrode coating method according to claim 6, characterized in that: The pole piece coating method further comprises: Drying the coated slurry to obtain a dry film; Acquiring position information of the mark, and detecting a third surface density of the substrate and the dry film corresponding to the mark position; The coating amount of the coating slurry is adjusted according to the third areal density.

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