Electrode plate floating powder detection assembly, detection method, control device and detection system

Abstract

The invention discloses an electrode plate floating powder detection assembly, a detection method, a control device and a detection system.The electrode plate floating powder detection assembly comprises a floating powder capturing layer, a pressing part and a linear motion driving device, and the floating powder capturing layer is used for being fixedly laid on a supporting platform and used for bearing a to-be-detected electrode plate; the pressing piece is used for being placed on the to-be-tested electrode slice; the linear motion driving device is used for being connected with one end of the to-be-detected electrode plate and pulling the to-be-detected electrode plate to move along the surface of the floating powder capturing layer, so that the pressing piece synchronously moves along with the to-be-detected electrode plate, and floating powder of the to-be-detected electrode plate falls off. Through the synergistic effect of the pressing piece and the linear motion driving device, the to-be-detected electrode plate and the floating powder capturing layer make relative motion in the state of keeping contact, natural falling of floating powder is achieved, the process is stable and repeatable, follow-up quantitative detection is facilitated, the floating powder amount of the electrode plate can be rapidly evaluated, and a reliable basis is provided for process optimization.

Description

Technical Field

[0001] This application relates to the field of battery technology, and in particular to an electrode sheet powder detection component, detection method, control device and detection system. Background Technology

[0002] During the preparation of lithium-ion battery electrode sheets, such as coating, drying, and rolling, uneven distribution of binder or stress release often results in the presence of loosely adhered active material particles on the surface, known as "floating powder." This floating powder may detach during subsequent winding, assembly, or use, causing safety and performance issues such as internal short circuits and increased self-discharge. Therefore, it is necessary to effectively detect and control the level of floating powder on the electrode sheets.

[0003] Currently, the characterization of powder floating on the surface of electrode sheets mainly falls into two categories. The first category involves indirect judgment by observing the degree of dirt on the table of the slicing or stacking equipment. This method is simple to operate, but it relies on manual visual assessment, is highly subjective, cannot be quantified, and is easily affected by human factors, leading to misjudgments. The second category involves immersing the electrode sheet in a solvent and analyzing the amount of floating powder by the mass difference before and after immersion. Although this method has higher accuracy, the process is cumbersome, time-consuming, and difficult to achieve rapid feedback. Summary of the Invention

[0004] This application provides an electrode sheet powder detection component, detection method, control device, and detection system, which can quantitatively and rapidly assess the amount of powder floating on the electrode sheet under test, thereby at least partially solving the above-mentioned technical problems.

[0005] To achieve the above objectives, according to a first aspect of this application, an electrode sheet powder detection assembly is provided, comprising: The powder capture layer is used to fix the material to the support platform and to support the electrode sheet to be tested. A holding element, used to place on the electrode sheet to be tested; A linear motion drive device is used to connect to one end of the electrode sheet to be tested and pull the electrode sheet to be tested along the surface of the powder capture layer, so that the holding member moves synchronously with the electrode sheet to be tested and causes the powder on the electrode sheet to fall off.

[0006] Optionally, the dust-catching layer comprises at least one of paper, nonwoven fabric, filter paper, or cotton cloth; and / or, The surface roughness Ra of the powder-capturing layer is between 1 μm and 10 μm.

[0007] Optionally, the pressure-holding element includes weights; and / or, The mass of the holding member is between 2 kg and 3 kg, and the contact area between the holding member and the electrode sheet to be tested is 20 mm. Up to 30 Between; and / or, In a direction perpendicular to the direction of movement of the electrode sheet under test, the ratio of the size of the holding member to the size of the electrode sheet under test is between 2 / 3 and 1.

[0008] Optionally, the linear motion drive device includes a tensile testing machine; and / or, The linear motion drive device has a clamp for holding one end of the electrode sheet to be tested in order to apply a pulling force to the electrode sheet.

[0009] Optionally, the electrode sheet powder detection assembly further includes a mass measuring device for measuring the mass of the electrode sheet under test.

[0010] According to a second aspect of this application, a method for detecting floating powder on an electrode sheet is provided, comprising: The electrode sheet to be tested is laid on the floating powder capture layer, and a pressing element is placed on the electrode sheet to be tested; The linear motion drive device pulls the electrode sheet under test along the surface of the powder capture layer, causing the holding member to move synchronously with the electrode sheet under test, and causing the powder on the electrode sheet under test to fall off.

[0011] Optionally, before the steps of laying the electrode sheet to be tested on the powder capture layer and placing the holding member on the electrode sheet to be tested, the steps of the electrode sheet powder detection method further include: The electrode sheet to be tested is obtained by cutting from the rolled electrode sheet; The electrode sheet to be tested is shaken to remove debris generated during the cutting process.

[0012] Optionally, the ratio of the distance the electrode under test is pulled to the dimension of the electrode under test in the direction of movement of the electrode under test is greater than or equal to 2 / 3 and less than 1.

[0013] Optionally, before the steps of laying the electrode sheet to be tested on the powder capture layer and placing the holding member on the electrode sheet to be tested, the steps of the electrode sheet powder detection method further include: measuring the first mass of the electrode sheet to be tested; After the step of moving the electrode sheet under test along the surface of the powder capture layer by a linear motion drive device, causing the holding member to move synchronously with the electrode sheet under test, and causing the powder on the electrode sheet under test to fall off, the electrode sheet powder detection method further includes: measuring the second mass of the electrode sheet under test.

[0014] Optionally, the first mass is The second mass is The mass of the holding member is M, the contact area between the holding member and the electrode sheet under test is S, and the distance the electrode sheet under test is pulled is L. When λ is less than or equal to a preset value, the electrode sheet under test is deemed qualified.

[0015] According to a third aspect of this application, a control device is provided, comprising a processor and a memory, wherein the memory stores a computer program, and when the computer program is executed by the processor, it implements the electrode sheet powder detection method as described in any of the above claims.

[0016] According to a fourth aspect of this application, an electrode sheet powder detection system is provided, comprising the control device as described above and the electrode sheet powder detection component as described in any one of the above.

[0017] In the electrode sheet powder detection component of this application embodiment, by setting up a powder capturing layer, a holding member, and a linear motion drive device, the electrode sheet under test is pulled, and the weight of the holding member maintains stable contact between its lower surface and the powder capturing layer. During the relative movement and contact between the electrode sheet under test and the powder capturing layer, the loosely attached powder on its surface naturally falls off due to disturbance. Based on this stable and repeatable powder removal process, the amount of powder can be quantitatively detected by subsequent measurement of the powder quality or the quality of the electrode sheet before and after powder removal. This solution overcomes the problems of strong subjectivity, roughness, and susceptibility to misjudgment due to human factors in visual judgment methods, and also avoids the shortcomings of solvent immersion methods, which are cumbersome, have long experimental cycles, and cannot quickly determine the quality. The powder amount obtained in this way can be used to evaluate the advantages and disadvantages of electrode sheet formulation design, coating method, and rolling process, supporting process optimization to obtain battery cells with better performance. In summary, this application utilizes the combined action of the holding component and the linear motion drive device to enable relative movement between the electrode sheet under test and the powder capture layer while maintaining contact, thereby achieving the natural shedding of the powder. This process is stable and repeatable, facilitating subsequent quantitative detection and enabling rapid assessment of the amount of powder on the electrode sheet, thus providing a reliable basis for process optimization.

[0018] Other features and advantages of this application will be described in detail in the following detailed description section. Attached Figure Description To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] To gain a more complete understanding of this application and its beneficial effects, the following description will be provided in conjunction with the accompanying drawings, wherein the same reference numerals in the following description denote the same parts.

[0020] Figure 1 This is a schematic diagram of the structure of the electrode sheet powder detection component provided in an exemplary embodiment of this disclosure; Figure 2 yes Figure 1 A top view of a portion of the structure of the electrode sheet powder detection component in the image; Figure 3 yes Figure 2 A schematic diagram of the electrode sheet powder detection component in the image when no holding element is placed; Figure 4 This is a schematic flowchart of the electrode sheet powder detection method provided in an exemplary embodiment of this disclosure.

[0021] Explanation of reference numerals in the attached figures: 100. Electrode sheet powder detection assembly; 1. Powder capture layer; 2. Holding component; 3. Linear motion drive device; 31. Fixture; 200. Support platform; 300. Electrode sheet to be tested. Detailed Implementation

[0022] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the protection scope of this application.

[0023] Please see Figures 1 to 3 This application provides an electrode sheet powder detection assembly 100, including a powder capturing layer 1, a holding member 2, and a linear motion drive device 3. The powder capturing layer 1 is used to be fixedly laid on a support platform 200 and to support the electrode sheet 300 to be tested. The holding member 2 is used to be placed on the electrode sheet 300 to be tested. The linear motion drive device 3 is used to connect to one end of the electrode sheet 300 to be tested and pull the electrode sheet 300 to be tested to move along the surface of the powder capturing layer 1, so that the holding member 2 moves synchronously with the electrode sheet 300 to be tested and causes the powder on the electrode sheet 300 to fall off.

[0024] The technical solution of this application, by setting up a powder-capturing layer 1, a holding member 2, and a linear motion drive device 3, ensures that the electrode sheet 300 under test, during the pulling process, utilizes the weight of the holding member 2 to maintain stable contact between its lower surface and the powder-capturing layer 1. During the relative movement and contact between the electrode sheet 300 and the powder-capturing layer 1, the loosely attached powder on its surface naturally falls off due to disturbance. Based on this stable and repeatable powder removal process, the amount of powder can be quantitatively detected by subsequently measuring the powder mass or the mass of the electrode sheet 300 before and after powder removal. This solution overcomes the problems of strong subjectivity, roughness, and susceptibility to misjudgment due to human factors in visual judgment methods, and also avoids the drawbacks of the solvent immersion method, which is cumbersome, has a long experimental cycle, and cannot provide rapid judgment. The obtained powder amount can be used to evaluate the advantages and disadvantages of electrode sheet formulation design, coating method, and rolling process, supporting process optimization to obtain higher-performance battery cells. In summary, this application achieves relative movement between the electrode sheet 300 under test and the powder capture layer 1 while maintaining contact through the coordinated action of the holding member 2 and the linear motion drive device 3, thereby enabling the natural shedding of the powder. This process is stable and repeatable, facilitating subsequent quantitative detection and allowing for rapid assessment of the amount of powder on the electrode sheet, thus providing a reliable basis for process optimization.

[0025] It should be noted that the "floating powder" detected in this application refers to loosely attached active material particles on the surface of the electrode sheet. These particles are not sufficiently anchored by the binder and are easily detached from the coating surface when subjected to slight external force. During battery production, such floating powder may detach due to vibration, contact, or other reasons during electrode sheet movement, conveying, or assembly, potentially adversely affecting the cleanliness control of subsequent processes and even increasing the risk of internal short circuits and self-discharge. Therefore, an ideal floating powder detection method should simulate the slight contact conditions in actual production as much as possible, assessing the tendency of floating powder to detach from the electrode sheet under normal use conditions, rather than causing coating damage through forceful scraping or peeling, thereby avoiding additional particle interference with the test results caused by mechanical damage.

[0026] Therefore, this application employs a "gentle disturbance" detection mechanism: by allowing relative sliding between the electrode sheet 300 under test and the powder capture layer 1 while maintaining stable contact, the slight interaction between the interfaces promotes the natural detachment of loosely attached powder. This process avoids applying strong forces or high-intensity contact, reducing the risk of damage to the coating of the electrode sheet 300 under test, and ensuring that the detached particles mainly originate from the originally poorly bonded powder, rather than additional dust introduced by the detection operation.

[0027] To achieve the aforementioned stable and controllable disturbance process, this application adopts a structural design of "fixing the powder capture layer 1, pressing the electrode sheet 300 under test, and pulling the electrode sheet 300 under test". The powder capture layer 1 is fixedly laid on the support platform 200, providing a stable bearing surface; the pressing member 2 is placed above the electrode sheet 300 under test, and its weight makes the electrode sheet 300 under test adhere to the surface of the powder capture layer 1, reducing the possibility of lifting, jumping or shifting during movement; the linear motion drive device 3 is connected to one end of the electrode sheet 300 under test and applies a pulling force, driving the electrode sheet 300 under test to slide smoothly along the surface of the powder capture layer 1, forming a continuous and uniform relative motion.

[0028] This design helps improve the repeatability and engineering applicability of the entire powder removal process. If the powder capture layer 1 is pulled instead, since it is usually a flexible thin material, it may elongate, wrinkle or shake under tension, which may lead to unstable contact with the powder capture layer 1, resulting in fluctuations in the intensity of action and affecting the consistency of powder removal. The powder capture layer 1 itself also has a certain degree of flexibility and deformation tendency. Without external pressure, it may shift, wrinkle or fold locally during movement, affecting the adhesion with the powder capture layer 1.

[0029] Therefore, the stabilizing effect of the holding member 2 and the synergistic effect of unidirectional pulling help to achieve smooth and continuous sliding of the electrode sheet 300 under test on the powder capture layer 1, forming a controllable, slightly disturbed environment. Under these conditions, the shedding of the powder mainly stems from its own weak bonding characteristics, rather than mechanical damage caused by the detection process. The amount of powder obtained can well reflect the actual cleanliness of the electrode sheet and can be used to evaluate the control level of processes such as coating and rolling. The technical solution of this application provides a non-destructive, easy-to-operate, and highly repeatable physical detection method. Through reasonable structural design, it achieves "stable contact, smooth movement, and gentle disturbance," enabling quantitative analysis of powder behavior without damaging the sample.

[0030] In some embodiments, the dust-capturing layer 1 comprises at least one of paper, nonwoven fabric, filter paper, or cotton cloth. In these embodiments, the selected material has a soft surface and no sharp structure, which can avoid scratching or damaging the surface coating of the electrode sheet 300 during relative movement, and prevent the introduction of additional dust due to the detection process itself, thereby ensuring that the detached particles only come from the loosely attached dust originally on the electrode sheet, improving the authenticity and accuracy of the detection results; at the same time, the above materials are low in cost, easy to obtain, and have good batch-to-batch consistency, which is conducive to maintaining the stability of the contact interface in different tests, supporting the repeatability of multiple tests and the reliability of process comparison.

[0031] In some embodiments, the dust-capturing layer 1 is ordinary printing paper. The printing paper has a smooth surface, uniform texture, and dense fiber structure, which can prevent scratching of the coating of the electrode sheet 300 during relative movement and prevent the introduction of additional dust due to the detection process itself; at the same time, the printing paper is inexpensive, readily available, and has stable performance between different batches, which is conducive to achieving repeatability of multiple tests and consistency of process comparison.

[0032] In some embodiments, the four corners of the printing paper are fixed to the support platform 200 with adhesive tape to prevent displacement or wrinkling during the detection process and to ensure the stability of the contact interface between the electrode sheet 300 under test and the capture layer.

[0033] In some embodiments, the surface roughness Ra of the powder capturing layer 1 is between 1 μm and 10 μm. In these embodiments, this roughness range can ensure effective contact between the electrode sheet 300 under test and the powder capturing layer 1 while avoiding the adverse effects of an excessively smooth or rough surface: if the surface roughness is too low (Ra < 1 μm), the contact interface is too smooth, which may result in insufficient disturbance of the powder on the surface of the electrode sheet 300 under test, preventing loosely attached particles from being fully detached and affecting the detection sensitivity; if the surface roughness is too high (Ra > 10 μm), the local protrusions may scratch the coating of the electrode sheet 300 under test, causing the active material to detach and interfering with the detection results. By controlling the surface roughness within the above range, this application can effectively disturb and release the loosely attached powder on the surface of the electrode sheet 300 under test without damaging the coating, thereby improving the authenticity and repeatability of the detection.

[0034] In some embodiments, the powder-catching layer 1 is printing paper, and the surface roughness Ra of the printing paper is between 2 μm and 6 μm.

[0035] In some embodiments, the holding member 2 includes a weight. In these embodiments, the weight provides uniform pressure with its precise and stable mass, ensuring reliable contact between the electrode sheet 300 under test and the powder capture layer 1 during movement. Since the weight is a standardized measuring instrument, its mass value is accurate and traceable, avoiding the pressure uncertainty caused by non-standard components, which helps improve the consistency and repeatability of the testing process. At the same time, as a commonly used laboratory item, the weight is readily available and requires no customization, reducing the implementation cost and assembly complexity of the testing components, making it suitable for R&D verification and rapid production line testing scenarios.

[0036] In some embodiments, the mass of the holding member 2 is between 2 kg and 3 kg, and the contact area between the holding member 2 and the electrode sheet 300 to be tested is 20 mm. Up to 30 In these embodiments, the combination of mass and contact area can ensure stable contact between the electrode sheet 300 under test and the powder capture layer 1 while avoiding adverse effects caused by excessive or insufficient pressure: if the mass is too small (<2 kg), the applied positive pressure is insufficient, which may result in insufficient static friction between the holding member 2 and the electrode sheet 300 under test to maintain synchronous movement. When the linear motion drive device 3 pulls the electrode sheet 300 under test, the holding member 2 cannot follow stably, resulting in slippage, displacement, or even overturning. This leads to uneven local force on the electrode sheet 300 under test, affecting the stability of its contact with the powder capture layer 1, and consequently causing insufficient powder shedding or uncontrollable detection process. If the mass is too large (>3 kg), it may cause local deformation of the electrode sheet 300 under test or cracking of the coating under pressure, and even damage to the unstable bonding structure after rolling, causing non-intrinsic dust to fall off and interfering with the authenticity of the detection results. At the same time, if the contact area is too small (<20 kg), Excessive pressure per unit area can easily cause localized stress concentration, increasing the risk of coating damage; if the contact area is too large (>30), it can also cause damage. This could lead to an excessively large coverage area for the holding element 2, affecting the smooth sliding of the electrode sheet 300 under test, or increasing operational complexity. The weight should be controlled between 2 kg and 3 kg, and the contact area should be controlled within 20 mm. ~30 Within the specified range, while ensuring that the holding member 2 moves synchronously with the electrode sheet 300 under test, full contact and controllable disturbance can be achieved, thereby improving the accuracy and repeatability of the test.

[0037] In some embodiments, the ratio of the size of the holding member 2 to the size of the electrode sheet 300 under test in a direction perpendicular to the direction of movement of the electrode sheet 300 under test is between 2 / 3 and 1. In these embodiments, this size ratio can ensure that the holding action uniformly covers the width of the electrode sheet 300 under test while avoiding the adverse effects of insufficient coverage or excessive extension: if the ratio is less than 2 / 3, the lateral coverage of the electrode sheet 300 under test by the holding member 2 is too narrow, which may lead to uneven pressure distribution and insufficient adhesion in the edge area, causing the electrode sheet 300 under test to warp or shift during movement, affecting its stability in contact with the powder capture layer 1; if the ratio is greater than 1, at least a part of the holding member 2 will extend beyond the edge of the electrode sheet 300 under test, and may directly contact the surface of the powder capture layer 1, generating additional frictional resistance during relative movement, resulting in poor sliding of the electrode sheet 300 under test, or even scratching the capture layer or causing the holding member 2 to jam, interfering with the stability of the detection process. By controlling the lateral dimension of the holding member 2 to the range of 2 / 3 to 1 of the size of the electrode sheet 300 under test, structural interference and motion blockage can be avoided while ensuring stable holding, thereby improving the reliability and repeatability of the testing process.

[0038] In some embodiments, the linear motion drive device 3 includes a tensile testing machine. In these embodiments, the tensile testing machine is a common piece of equipment in laboratories or quality inspection departments, capable of providing a constant and adjustable tensile force, and ensuring that the electrode sheet 300 under test makes smooth linear motion along a preset path, avoiding speed fluctuations or directional deviations, which is beneficial to achieving standardization and repeatability of the testing process.

[0039] In other embodiments, the linear motion drive device 3 is a stepper motor coupled with a lead screw transmission mechanism. In these embodiments, the stepper motor can be precisely adjusted in speed by a controller, thereby controlling the moving speed of the electrode sheet 300 under test to achieve uniform, low-speed, linear motion; the lead screw transmission mechanism has the characteristics of high transmission accuracy, small backlash, and smooth operation, which can ensure that the trajectory of the electrode sheet 300 under test is stable and without deviation during the movement.

[0040] In some embodiments, the linear motion drive device 3 has a clamp 31 for clamping one end of the electrode sheet 300 to be tested, so as to apply a pulling force to the electrode sheet 300. In these embodiments, the clamp 31 enables quick connection and disconnection between the electrode sheet 300 to be tested and the drive device, improving detection efficiency; at the same time, the stable clamping of the end of the electrode sheet 300 by the clamp 31 helps to keep the line of action of the pulling force consistent with the direction of movement, ensuring that the electrode sheet 300 is subjected to uniform force and has a straight trajectory during movement, avoiding force transmission deviation, slippage or torsion caused by indirect connection methods such as ropes or tapes; in addition, the clamp 31 can be adapted to clamp the two sides of the electrode sheet 300 to further improve the stability during movement, prevent displacement or wrinkling, and ensure the continuity and consistency of its contact interface with the powder capture layer 1.

[0041] In some embodiments, the electrode sheet dust detection assembly 100 further includes a mass measuring device for measuring the mass of the electrode sheet 300 under test. In these embodiments, the mass of dust detached from the surface of the electrode sheet 300 is obtained by comparing the mass change of the electrode sheet 300 before and after relative movement with the dust capturing layer 1. This method is calculated directly based on the mass loss of the object under test, without relying on the dust collection efficiency, avoiding measurement deviations caused by dust scattering, adsorption, or residue. It is particularly suitable for scenarios with small amounts of dust or high requirements for detection accuracy, and is beneficial for achieving highly sensitive dust level assessment.

[0042] In other embodiments, when the floating powder can be effectively collected into the floating powder capturing layer 1 (e.g., by setting up a barrier structure in the collection area), a mass measuring device is used to measure the mass of the floating powder capturing layer 1 before and after capturing the floating powder. In these embodiments, the mass of the detached floating powder can be determined by obtaining the mass increment of the floating powder capturing layer 1.

[0043] Please see Figure 4According to a second aspect of this disclosure, a method for detecting floating powder on an electrode sheet is provided, comprising: S400: The electrode sheet 300 to be tested is laid on the floating powder capture layer 1, and the holding member 2 is placed on the electrode sheet 300 to be tested; S500: The linear motion drive device 3 pulls the electrode sheet 300 under test along the surface of the powder capture layer 1, so that the holding member 2 moves synchronously with the electrode sheet 300 under test, and causes the powder on the electrode sheet 300 under test to fall off.

[0044] In these embodiments, in step S400, the electrode sheet 300 under test is in direct contact with the powder capture layer 1. The holding member 2 applies vertical pressure to the electrode sheet 300 under test with its preset mass to ensure that the electrode sheet 300 under test remains stably attached to the powder capture layer 1 during subsequent relative movement. This pressure is provided by the weight of the holding member 2 itself, without the need for an external loading mechanism, making operation simple and the pressure uniform. In step S500, the linear motion drive device 3 applies a pulling force to one end of the electrode sheet 300 under test through the clamp 31 or the connector, causing it to make a smooth linear movement along the surface of the powder capture layer 1. During this process, the loosely attached powder on the surface of the electrode sheet 300 under test is effectively detached under the disturbance. This method can simulate slight disturbances during actual production or use without damaging the coating of the electrode sheet 300 under test, only causing the floating powder to fall off, avoiding the introduction of new dust due to scratching, cracking, etc. At the same time, the whole process is repeatable and the parameters are controllable, which is conducive to the standardized comparison of the floating powder level of different batches of electrode sheets 300 under test, and improves the authenticity, sensitivity and reliability of the test results and process evaluation.

[0045] In steps S400 and S500, to achieve a stable and controllable powder shedding process, the electrode sheet powder detection method can be implemented using the electrode sheet powder detection assembly 100 of any of the embodiments described above. It should be understood that the following examples are only used to illustrate a typical implementation of this method and are not the only limitation of the method. For example, in the specific implementation of this method: at least one of paper, non-woven fabric, filter paper, or cotton cloth with a surface roughness Ra of 1 μm to 10 μm is fixed on the support platform 200 as the powder capture layer 1; a powder weighing 2 kg to 3 kg with a contact area of ​​20 mm is used as the powder capture layer 1. Up to 30 A weight is placed above the electrode sheet 300 to be tested as a holding member 2, ensuring that its dimension perpendicular to the direction of movement covers more than 2 / 3 of the width of the electrode sheet 300. A tensile testing machine or a stepper motor with a lead screw transmission mechanism is used to connect and pull the electrode sheet 300, allowing it to slide smoothly along the surface of the capture layer. With this configuration, this method can promote the natural shedding of loosely attached powder without damaging the electrode sheet coating, and the amount of powder obtained can better reflect the actual cleanliness of the electrode sheet.

[0046] In some embodiments, before the steps of laying the electrode sheet 300 to be tested on the powder capture layer 1 and placing the retainer 2 on the electrode sheet 300 to be tested, the steps of the electrode sheet powder detection method further include: S100: The electrode sheet to be tested 300 is obtained by cutting from the rolled electrode sheet; S200: The electrode sheet 300 to be tested is shaken to remove debris generated during the cutting process.

[0047] In these embodiments, step S100 obtains a uniformly shaped and sized electrode sheet 300 through a cutting operation, which facilitates clamping, pressing, and motion control during subsequent testing, improves the consistency of test conditions among multiple batches of samples, and achieves standardized comparison. The shaking process in step S200 aims to remove debris generated by chipping or burr removal at the cutting edges. This debris is not loose, adhering powder naturally present on the electrode sheet 300 after the rolling process. If not removed beforehand, it may be misidentified as "powder" during subsequent testing, leading to inflated test results and affecting the judgment of the true powder level. Gentle shaking (such as a light hand shake) effectively releases debris without damaging the coating structure of the electrode sheet 300, ensuring that subsequent testing only reflects the powder that may fall off the electrode sheet surface under actual working conditions, improving the authenticity of the test results and the accuracy of process evaluation.

[0048] In some embodiments, the ratio of the distance the test electrode 300 is pulled to the dimension of the test electrode 300 in the direction of movement is greater than or equal to 2 / 3 and less than 1. In these embodiments, this stroke ratio ensures sufficient detachment of floating powder while avoiding structural instability caused by excessive pulling stroke. If the pulling distance is too short (ratio less than 2 / 3), the area where the test electrode 300 and the floating powder capturing layer 1 slide relative to each other is limited, the floating powder disturbance range is insufficient, and some loosely attached particles may fail to detach, resulting in a lower detection result. Controlling the pulling distance within the range of 2 / 3 to less than 1 of the length of the test electrode 300 ensures that most of the surface undergoes effective disturbance while reserving sufficient safety margin (ratio less than 1) for the clamping end and pressing area, maintaining the continuity of pressure and tension throughout the detection process, and improving the representativeness of floating powder detachment and the reliability of the detection process.

[0049] In some embodiments, before step S400: laying the electrode sheet 300 to be tested on the floating powder capturing layer 1 and placing the holding member 2 on the electrode sheet 300 to be tested, the electrode sheet floating powder detection method further includes: S300: Measure the first mass of the electrode sheet 300 under test; In step S500: after the step of moving the electrode sheet 300 to be tested along the surface of the powder capture layer 1 by the linear motion drive device 3, causing the holding member 2 to move synchronously with the electrode sheet 300 to be tested, and causing the powder on the electrode sheet 300 to fall off, the steps of the electrode sheet powder detection method further include: S600: Measure the second mass of the electrode sheet 300 under test.

[0050] In these embodiments, the mass of the electrode sheet 300 before and after powder removal is obtained. By comparing the mass change of the electrode sheet 300 before and after powder removal (i.e., the difference between the first mass and the second mass), the total mass of the floating powder detached from its surface can be directly calculated. This method does not rely on the collection efficiency or uniformity of the floating powder on the capture layer, avoiding measurement deviations caused by floating powder scattering, electrostatic adsorption, or residue in the support structure. Even for cases with a small amount of floating powder, this method can still accurately capture minute mass changes using a high-precision mass measurement device (such as a 0.00001g electronic balance), improving detection sensitivity. Furthermore, this method has a simple operation process and strong data traceability, which is conducive to the standardization and quantitative comparison of floating powder levels of different batches of electrode sheets 300, providing a reliable basis for the optimization of electrode sheet production processes and quality control.

[0051] In some embodiments, the first mass is The second mass is The mass of the holding member 2 is M, the contact area between the holding member 2 and the electrode sheet 300 under test is S, and the distance the electrode sheet 300 under test is pulled is L. When λ is less than or equal to the preset value, the electrode sheet 300 under test is deemed qualified.

[0052] In these embodiments, a normalized index characterizing the degree of powder shedding—the powder release rate λ—is calculated based on the above parameters, and its definition is as follows: ,in, λ represents the mass difference of the electrode sheet 300 before and after powder removal, i.e., the total mass of the detached powder; S represents the contact area between the holding member 2 and the electrode sheet 300, reflecting the size of the force-bearing area; M represents the mass of the holding member 2, representing the applied pressure level; and L represents the pulling distance, representing the disturbance stroke. The powder release rate λ comprehensively reflects the powder removal capacity under unit pressure (M / S) and unit stroke L. By dividing the powder mass by M*L and multiplying by the contact area S, this indicator effectively eliminates the differences in test results caused by differences in the mass of the holding member 2, the contact area, or the pulling distance, making the data obtained under different test conditions comparable. For example, when using holding members 2 of different sizes or different pulling distances, this formula can still be used for standardized comparison to avoid misjudgment caused by fluctuations in test parameters. Furthermore, a preset value is set. When the calculated powder release rate λ is less than or equal to the preset value, the electrode sheet 300 is judged to be qualified; otherwise, it is unqualified. This judgment method not only considers the absolute amount of floating powder, but also combines the test conditions (pressure and stroke), realizing the standardized and quantitative evaluation of the looseness of floating powder on the surface of the electrode sheet 300 under test, which is conducive to the consistent control of electrode sheet quality under different batches, different production lines or different process parameters.

[0053] In some embodiments, the preset value is 0.5 ppm m / kg. Specifically, in these embodiments, when the calculated powder release rate λ ≤ 0.5 ppm m / kg, the quality of the electrode sheet 300 under test can be determined to meet the standard requirements. This preset value is determined based on a large amount of experimental data and actual production experience, and aims to balance the relationship between the allowable fluctuations in the production process and the product quality requirements.

[0054] This application also provides a control device, which includes a processor and a memory. The memory stores a computer program, and when the computer program is executed by the processor, it implements the electrode sheet powder detection method as described in any of the above embodiments.

[0055] A processor can perform various actions and processes according to a computer program stored in memory. Specifically, a processor can be an integrated circuit chip with signal processing capabilities. The aforementioned processor can be a general-purpose processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), an off-the-shelf programmable gate array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components, capable of implementing or executing the methods, steps, and logic block diagrams disclosed in the embodiments of this application. A general-purpose processor can be a microprocessor or any conventional processor, and can be based on an x86 architecture or an ARM architecture.

[0056] The memory can be volatile or non-volatile, or may include both. Non-volatile memory can be read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), or flash memory. Volatile memory can be random access memory (RAM) used as an external cache. By way of example, but not limitation, many forms of RAM are available, such as static random access memory (SRAM), dynamic random access memory (DRAM), synchronous dynamic random access memory (SDRAM), double data rate synchronous dynamic random access memory (DDRSDRAM), enhanced synchronous dynamic random access memory (ESDRAM), synchronous linked dynamic random access memory (SLDRAM), and direct memory bus random access memory (DRRAM). It should be noted that the memory used in the methods described herein is intended to include, but is not limited to, these and any other suitable types of memory.

[0057] In practice, the processor is configured to execute the following control logic: For example, the processor is configured to control the linear motion drive device 3 to pull the electrode sheet 300 under test along the surface of the powder capture layer 1 until the ratio of the pulling distance L of the electrode sheet 300 under test to its size in the direction of motion reaches a set range (e.g., greater than or equal to 2 / 3 and less than 1), and then issue a stop command. For example, the processor is configured to receive the first mass of the electrode sheet 300 under test before powder removal, collected by the quality measurement device. and the second quality after powder removal The powder release rate is calculated by combining the pre-stored mass M of the holding member 2, the contact area S between the holding member 2 and the electrode sheet 300 under test, and the pulling distance L of the electrode sheet 300 under test. When the calculated result λ ≤ the preset value (e.g., 0.5 ppm m / kg), the electrode sheet to be tested is deemed qualified and the test conclusion is output.

[0058] This system automates the detection process and standardizes the judgment by embedding key steps of the detection method into the control logic, thereby improving detection efficiency and result consistency.

[0059] This application also provides an electrode sheet powder detection system, including an electrode sheet powder detection component 100 and a control device. The structure of the electrode sheet powder detection component 100 is as described in any of the above embodiments, and the configuration of the control device is as described in any of the above embodiments. Specifically, the control device can receive parameter information related to the detection process (including but not limited to the mass of the electrode sheet 300 before and after powder removal, the mass M of the holding member 2, the holding contact area S, and the pulling distance L), and calculate the powder release rate λ based on the parameter information. When λ ≤ a preset threshold (e.g., 0.5 ppm·m / kg), the electrode sheet 300 is determined to be qualified, and the corresponding detection conclusion is output. The parameter information can be obtained through automatic acquisition, manual input, or import from external devices, and its data source or transmission method is not limited. In addition, the control device can also support the configuration of detection parameters (such as pulling speed, stroke ratio, holding conditions, etc.) to adapt to the detection needs of different material systems (such as lithium iron phosphate, ternary materials) or electrode sheets of different specifications. By combining the electrode powder detection component 100 provided in this application with a control device having the above-mentioned logic processing capabilities, the system can achieve standardized and quantitative assessment of powder quantity while ensuring non-destructive operation and ease of use. It is suitable for various application scenarios such as R&D verification, process debugging and production line quality monitoring.

[0060] The following section, based on actual test data, further explains the application of the electrode sheet powder detection method and its evaluation indicators disclosed herein.

[0061] Example: Comparison of powder floating levels in negative electrode sheets with different SBR ratios.

[0062] Using the same active material system and current collector, three sets of negative electrode sheets were prepared by adjusting the distribution ratio of the water-based binder SBR (styrene-butadiene rubber) in the double-layer coating, denoted as Scheme A, B, and C, respectively. The SBR ratios in each scheme are as follows: in Scheme A, the SBR content in the upper and lower layers is similar; in Scheme B, the SBR content in the upper layer is higher than that in the lower layer; and in Scheme C, the SBR content in the upper layer is lower than that in the lower layer. All samples underwent coating and rolling processes under the same conditions to ensure consistency in key parameters such as areal density, compaction density, and drying temperature, thereby eliminating non-variable interference.

[0063] Select the rolled plates and cut each plate into sizes. The elongated electrode sheet 300 to be tested was shaken to remove debris generated during the cutting process; the first mass of the electrode sheet 300 before powder removal was measured using an analytical balance. Then, the powder removal operation was performed: the electrode sheet 300 to be tested was laid flat on the powder capturing layer 1 made of printing paper, and the powder capturing layer 1 was fixed to the support platform 200 with tape; a 2.2 kg mass and a base area of ​​[missing information] were placed on the surface of the electrode sheet 300 to be tested. A rectangular clamping member 2 is used; a tensile testing machine is used to clamp one end of the electrode sheet 300 to be tested at approximately 1 / 10 of its length direction using grippers, and a constant tensile force of 100 N is applied to move the electrode sheet 300 to be tested along the surface of the powder capture layer 1 at a uniform speed, ensuring that the clamping member 2 always moves synchronously with the electrode sheet 300 to be tested. The pulling distance is controlled to be 300 mm. After the pulling is completed, the clamping member 2 is removed, the electrode sheet 300 to be tested is removed, and the second mass of the electrode sheet 300 to be tested is measured again using an analytical balance. Finally, the powder release rate λ was calculated using the aforementioned formula. Three experiments were conducted for each type of electrode sheet, and the average value was calculated for comparison. The test results are as follows:

[0064] The test results show that the electrode sheets produced by the three schemes are all qualified. The difference in surface powder level can be clearly distinguished by the powder release rate (λ). Among them, Scheme A has the lowest compaction rate, indicating that it has the least powder detachment. This is attributed to the more balanced SBR ratio in the double-layer coating, which makes the binder more evenly distributed throughout the coating thickness direction, effectively enhancing the bonding strength between the active particles and the current collector and reducing the presence of loosely attached particles. In contrast, Schemes B and C have uneven SBR distribution, especially with a higher concentration on the surface, which may lead to insufficient bonding of the underlying layer or a decrease in interfacial adhesion, making them more prone to powder detachment under mechanical disturbance. This embodiment verifies that the method disclosed in this paper can not only quantitatively identify the powder level, but also sensitively reflect the impact of slurry formulation and coating process on the final product quality, and has good discrimination ability and process guidance value.

[0065] In the description of this application, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more features. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0066] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0067] The embodiments, implementation methods, and related technical features of this application can be combined and substituted for each other without conflict.

[0068] The above are merely preferred embodiments of this application and are not intended to limit this application in any way. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of this application without departing from the scope of the technical solution of this application shall still fall within the scope of the technical solution of this application.

Claims

1. An electrode sheet powder detection component, characterized in that, include: The powder capture layer is used to fix the material to the support platform and to support the electrode sheet to be tested. A holding element, used to place on the electrode sheet to be tested; A linear motion drive device is used to connect to one end of the electrode sheet to be tested and pull the electrode sheet to be tested along the surface of the powder capture layer, so that the holding member moves synchronously with the electrode sheet to be tested and causes the powder on the electrode sheet to fall off.

2. The electrode sheet powder detection assembly according to claim 1, characterized in that, The dust-catching layer comprises at least one of paper, non-woven fabric, filter paper, or cotton cloth; and / or, The surface roughness Ra of the powder-capturing layer is between 1 μm and 10 μm.

3. The electrode sheet powder detection assembly according to claim 1, characterized in that, The pressure-holding element includes weights; and / or, The mass of the holding member is between 2 kg and 3 kg, and the contact area between the holding member and the electrode sheet to be tested is 20 mm. Up to 30 Between; and / or, In a direction perpendicular to the direction of movement of the electrode sheet under test, the ratio of the size of the holding member to the size of the electrode sheet under test is between 2 / 3 and 1.

4. The electrode sheet powder detection assembly according to claim 1, characterized in that, The linear motion drive device includes a tensile testing machine; and / or... The linear motion drive device has a clamp for holding one end of the electrode sheet to be tested in order to apply a pulling force to the electrode sheet.

5. The electrode sheet powder detection assembly according to any one of claims 1 to 4, characterized in that, The electrode sheet powder detection assembly also includes a mass measuring device, which is used to measure the mass of the electrode sheet to be tested.

6. A method for detecting floating powder on electrode sheets, characterized in that, include: The electrode sheet to be tested is laid on the floating powder capture layer, and a pressing element is placed on the electrode sheet to be tested; The linear motion drive device pulls the electrode sheet under test along the surface of the powder capture layer, causing the holding member to move synchronously with the electrode sheet under test, and causing the powder on the electrode sheet under test to fall off.

7. The method for detecting floating powder on electrode sheets according to claim 6, characterized in that, Before the steps of laying the electrode sheet to be tested on the floating powder capture layer and placing the holding member on the electrode sheet to be tested, the steps of the electrode sheet floating powder detection method further include: The electrode sheet to be tested is obtained by cutting from the rolled electrode sheet; The electrode sheet to be tested is shaken to remove debris generated during the cutting process.

8. The method for detecting floating powder on electrode sheets according to claim 6, characterized in that, The ratio of the distance the electrode under test is pulled to the dimension of the electrode under test in the direction of movement of the electrode under test is greater than or equal to 2 / 3 and less than 1.

9. The method for detecting floating powder on electrode sheets according to claim 6, characterized in that, Before the steps of laying the electrode sheet to be tested on the floating powder capture layer and placing the holding member on the electrode sheet to be tested, the steps of the electrode sheet floating powder detection method further include: measuring the first mass of the electrode sheet to be tested; After the step of moving the electrode sheet under test along the surface of the powder capture layer by a linear motion drive device, causing the holding member to move synchronously with the electrode sheet under test, and causing the powder on the electrode sheet under test to fall off, the electrode sheet powder detection method further includes: measuring the second mass of the electrode sheet under test.

10. The method for detecting floating powder on electrode sheets according to claim 9, characterized in that, The first mass is The second mass is The mass of the holding member is M, the contact area between the holding member and the electrode sheet under test is S, and the distance the electrode sheet under test is pulled is L. When λ is less than or equal to a preset value, the electrode sheet under test is deemed qualified.

11. A control device, characterized in that, It includes a processor and a memory, wherein the memory stores a computer program, and when the computer program is executed by the processor, it implements the electrode sheet powder detection method as described in any one of claims 6 to 10.

12. A system for detecting floating powder on electrode sheets, characterized in that, It includes the control device as described in claim 11, and the electrode sheet powder detection component as described in any one of claims 1 to 5.

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