Tab smoothing system for battery cell winding

Abstract

The invention relates to the technical field of battery manufacturing, in particular to a tab flattening system for battery cell winding, which is provided with a flattening control module, a feature acquisition module, a pre-analysis module, a surface analysis module and a flattening compensation module. The pre-analysis module is used for marking first abnormal corrugations and determining pressure parameters of a smoothing roller for pre-smoothing the tab, the surface analysis module is used for marking second abnormal corrugations and screening characteristic abnormal corrugations, whether pre-smoothing is effective or not is judged, and the smoothing compensation module is used for determining corrugation trend parameters and determining a smoothing adjustment mode for smoothing the tab. According to the tab flattening system and the tab flattening method, the pre-flattening parameters are adjusted according to the real-time abnormal characteristics of the surfaces of the tabs, the flattening parameters are adaptively adjusted according to the comparison condition of the abnormal surfaces of the tabs before and after pre-flattening, and the reliability of the tab flattening system for battery cell winding is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of battery manufacturing, and in particular to a tab smoothing system for battery cell winding. Background Art

[0002] In the battery cell winding process, the state of the tab plays a vital role in the quality of the battery cell. As the core component of the battery, the performance of the battery cell is closely related to the flatness of the tab. The tab is the key part connecting the battery cell to the external circuit. If the tab has problems such as wrinkles, skewness or folding, it will affect the stability and consistency of the electrical connection of the battery cell. During the battery charging and discharging process, uneven tabs will lead to uneven current distribution and increased local resistance, which will cause heat generation, reduce the battery charging and discharging efficiency, shorten the battery life, and even in extreme cases, cause safety hazards such as overheating and fire. During the battery cell winding process, it is common for the tab to be in a bad state. On the one hand, the material characteristics of the tab itself make it easy to deform during the processing. On the other hand, problems left over from the previous process will also lead to poor tab condition, which will be brought into the winding process. During the winding process, the tab will also be affected by the winding tension, causing it to be excessively warped, folded or wrinkled. Existing tab smoothing technology has many limitations. Traditional tab smoothing devices use fixed structures, such as roller groups with fixed pressure or angle. They cannot be dynamically adjusted according to the real-time abnormal distribution, direction and length of the tab surface, nor can they make targeted adjustments to the smoothing parameters to destroy the stress concentration trend, resulting in repeated tab anomalies and difficulty in achieving effective tab smoothing. At the same time, traditional tab smoothing systems often rely on the operator's experience or a lot of trial and error in parameter adjustment, and lack quantification based on the geometric characteristics of tab anomalies, resulting in insufficient parameter adjustment accuracy and unable to meet high production standards. Therefore, improving the reliability of the tab smoothing system used for battery cell winding is a technical problem that needs to be solved urgently.

[0003] For example, China Patent Authorization Announcement No.: CN114388894B, the invention discloses a tab smoothing mechanism and a battery cell processing system, the tab smoothing mechanism has a fixing part, the fixing part is arranged on one side of the end of the core with the tab, the fixing part has a guide surface facing the end of the core, the distance between the guide surface and the end of the core with the tab gradually decreases from the feed end to the discharge end, therefore, the tab moves relative to the fixing part as the core is wound, when passing through the guide surface, the tab is squeezed by the guide surface toward the end of the core, after being squeezed by the guide surface, the tab can bend toward the end face of the core, thereby improving the winding quality of the core.

[0004] The following problems also exist in the prior art: The existing technology does not take into account that fixed, single smoothing parameters are difficult to adapt to abnormal conditions on the tab surface, which affects the efficiency and reliability of tab smoothing and is difficult to meet high production standards. The existing technology cannot adjust the pre-smoothing parameters according to the real-time abnormal characteristics of the tab surface, and cannot adaptively adjust the smoothing parameters according to the comparison of the tab surface abnormalities before and after pre-smoothing, which affects the reliability of the tab smoothing system used for battery cell winding. Summary of the Invention

[0005] To this end, the present invention provides a tab smoothing system for battery cell winding, which is used to overcome the problem that the prior art cannot adjust the pre-smoothing parameters according to the real-time abnormal characteristics of the tab surface, and cannot adaptively adjust the smoothing parameters according to the comparison of the tab surface abnormalities before and after pre-smoothing, thereby affecting the reliability of the tab smoothing system for battery cell winding.

[0006] To achieve the above objectives, the present invention provides a tab smoothing system for battery cell winding, comprising: a smoothing control module, comprising a first smoothing unit for pre-smoothing the tab, and a second smoothing unit for smoothing the tab; a feature acquisition module connected to the smoothing control module, for acquiring a first surface image of the tab before pre-smoothing and a second surface image after pre-smoothing; a pre-analysis module, connected to the smoothing control module and the feature acquisition module, respectively, for marking a first abnormal ripple based on the first surface image of the tab, and determining a pre-smoothing smoothing roller pressure parameter based on a ripple distribution parameter and a ripple extension parameter; a surface analysis module, connected to the feature acquisition module and the pre-analysis module, respectively, for marking a second abnormal ripple based on the second surface image of the tab, and screening characteristic abnormal ripples based on the first abnormal ripples and the second abnormal ripples to determine whether the pre-smoothing is effective; A smoothing compensation module is respectively connected to the smoothing control module and the surface analysis module, and is used to determine the ripple trend parameters according to the first abnormal ripple and the characteristic abnormal ripple based on the judgment result that pre-smoothing is invalid, so as to determine that the smoothing adjustment method for smoothing the tab is to apply high-frequency pulse pressure to the smoothing roller, determine the pulse frequency of the high-frequency pulse pressure based on the ripple trend parameters, or adjust the angle between the smoothing roller and the tab, and determine the increase in the angle according to the ripple extension factor and the ripple distribution parameters of the second surface image.

[0007] Furthermore, the pre-analysis module is used to determine the ripple distribution parameter and the ripple extension parameter, wherein: The pre-analysis module is used to calculate the distance between the midpoint of any first abnormal ripple and the midpoints of the other first abnormal ripples, and determine the variance of the distance as the ripple distribution parameter; The ripple extension parameter is an average value of the distances between the endpoints of each first abnormal ripple.

[0008] Furthermore, the pre-analysis module is used to determine the smoothing roller pressure parameters for pre-smoothing the tab, wherein: The pressure parameters of the smoothing roller for pre-smoothing the tab are respectively positively correlated with the corrugation distribution parameter and the corrugation extension parameter.

[0009] Furthermore, the surface analysis module is used to screen the characteristic abnormal ripples, wherein: The surface analysis module selects the second abnormal ripple as a characteristic abnormal ripple based on a determination result that the first abnormal ripple and the second abnormal ripple meet the characteristic abnormal ripple condition; The characteristic abnormal ripple condition is that the second abnormal ripple does not exist in the first surface image.

[0010] Furthermore, the surface analysis module is used to determine whether the pre-smoothing is effective, wherein: The surface analysis module determines that the pre-smoothing is invalid based on a determination result that the characteristic abnormal ripples meet a pre-smoothing invalidation condition; The pre-smoothing invalidation condition is that the area of the characteristic abnormal ripple exceeds a preset area threshold.

[0011] Furthermore, the smoothing compensation module is used to determine a first ripple trend vector and a characteristic ripple trend vector, wherein: The smoothing compensation module uses any endpoint of the first abnormal ripple as a vector starting point, calculates the interval distances between the remaining endpoints on the first abnormal ripple and the endpoint, constructs a first ripple vector with the endpoint with the maximum interval distance as the vector end point, and determines the vector obtained by adding the first ripple vectors as the first ripple trend vector; Taking any endpoint of the characteristic abnormal ripple as the starting point of the vector, calculate the interval distance between the remaining endpoints on the characteristic abnormal ripple and the endpoint, and construct a characteristic ripple vector with the endpoint with the maximum interval distance as the vector end point. The vector obtained by adding up the characteristic ripple vectors is determined as the characteristic ripple trend vector.

[0012] Furthermore, the smoothing compensation module is used to determine the ripple trend parameter, wherein: The smoothing compensation module calculates a vector angle between the first ripple trend vector and the characteristic ripple trend vector, and determines the vector angle as a ripple trend parameter.

[0013] Furthermore, the smoothing compensation module is used to determine a smoothing adjustment method for smoothing the tab, wherein: If the ripple trend parameter meets the determination result of the pulse smoothing condition, the smoothing compensation module determines that the smoothing adjustment method for smoothing the tab is to apply high-frequency pulse pressure to the smoothing roller, and determines the pulse frequency of the high-frequency pulse pressure based on the ripple trend parameter; If the ripple trend parameter does not meet the determination result of the pulse smoothing condition, the smoothing compensation module determines that the smoothing adjustment method for smoothing the tab is to adjust the angle between the smoothing roller and the tab, and determines the increase amount of the angle according to the ripple extension factor and the ripple distribution parameter of the second surface image; The pulse smoothing condition is that the ripple trend parameter exceeds a preset ripple trend parameter threshold.

[0014] Furthermore, the smoothing compensation module is used to determine the pulse frequency of the high-frequency pulse pressure, wherein the pulse frequency is positively correlated with the ripple trend parameter.

[0015] Furthermore, the smoothing compensation module is used to determine the increase in the angle between the smoothing roller and the tab, and the increase in the angle is positively correlated with the corrugation distribution parameter and the corrugation extension factor, respectively, wherein, The smoothing compensation module is used to determine the component vector of the characteristic corrugation vector in the direction parallel to the length of the tab as the first component vector, determine the component vector of the characteristic corrugation vector in the direction perpendicular to the length of the tab as the second component vector, calculate the ratio of the modulus of the first component vector to the modulus of the second component vector, and determine the average value of the ratio as the corrugation extension factor.

[0016] Compared with the prior art, the beneficial effect of the present invention lies in that the present invention sets a smoothing control module, a feature acquisition module, a pre-analysis module, a surface analysis module, and a smoothing compensation module, and obtains the surface images of the tab before and after pre-smoothing through the feature acquisition module, marks the first abnormal ripple through the pre-analysis module, and determines the smoothing roller pressure parameters for pre-smoothing the tab, marks the second abnormal ripple through the surface analysis module, screens the characteristic abnormal ripples, and determines whether the pre-smoothing is effective, and determines the ripple trend parameters according to the first abnormal ripple and the characteristic abnormal ripple through the smoothing compensation module, and determines the smoothing adjustment method for smoothing the tab, thereby realizing the adjustment of the pre-smoothing parameters according to the real-time abnormal characteristics of the tab surface, and adaptively adjusting the smoothing parameters according to the comparison of the tab surface abnormalities before and after pre-smoothing, thereby improving the reliability of the tab smoothing system for battery cell winding.

[0017] In particular, the present invention determines the smoothing roller pressure parameters for pre-smoothing the tabs based on the ripple distribution parameters and the ripple extension parameters through a pre-analysis module. It can be understood that by determining the smoothing roller pressure parameters based on the ripple distribution parameters and the ripple extension parameters, dynamic and precise regulation of the smoothing roller pressure can be achieved. By quantifying the uniformity of the ripple distribution and the length characteristics of the ripples, the smoothing roller pressure parameters for pre-smoothing the tabs are adaptively adjusted to avoid the problems of insufficient pressure or excessive pressure caused by traditional experience-based parameter adjustment, thereby improving the consistency and efficiency of tab smoothing, adapting to the abnormal differences of different batches of tabs, reducing tab damage and equipment wear caused by improper pressure, and improving production yield and equipment service life. The present invention determines the smoothing roller pressure parameters for pre-smoothing the tabs based on the ripple distribution parameters and the ripple extension parameters through a pre-analysis module, thereby achieving adjustment of the pre-smoothing parameters according to the real-time abnormal characteristics of the tab surface, thereby improving the reliability of the tab smoothing system for battery cell winding.

[0018] In particular, the present invention uses a surface analysis module to screen characteristic abnormal ripples based on the first abnormal ripples and the second abnormal ripples to determine whether pre-smoothing is effective. It can be understood that by comparing the surface ripples of the tab before and after pre-smoothing, it is possible to identify whether new ripples appear after pre-smoothing, and to analyze the surface condition of the tab in more detail, thereby judging the effectiveness of the pre-smoothing operation, improving production efficiency, quickly determining the pre-smoothing effect, and adjusting the smoothing parameters in time to reduce production interruptions or defective products caused by improper smoothing, thereby improving overall production efficiency, promptly discovering and correcting problems in the smoothing process, and avoiding the scrapping of the tab due to ineffective smoothing, thereby reducing production costs. The present invention uses a surface analysis module to screen characteristic abnormal ripples based on the first abnormal ripples and the second abnormal ripples to determine whether pre-smoothing is effective. Furthermore, it realizes the determination of whether pre-smoothing is effective based on the comparison of the abnormalities on the tab surface before and after pre-smoothing, thereby improving the reliability of the tab smoothing system for battery cell winding.

[0019] In particular, the present invention determines the ripple trend parameters according to the first abnormal ripple and the characteristic abnormal ripple through the smoothing compensation module to determine the smoothing adjustment method for smoothing the pole ear. It can be understood that by constructing the ripple trend vector and calculating the vector angle, the change in the direction of the pole ear wrinkles before and after pre-smoothing can be quantified, providing a reliable basis for selecting a suitable smoothing strategy. Two different smoothing adjustment methods are determined according to whether the ripple trend parameters meet the pulse smoothing conditions. The targeted strategy can better adapt to different types of wrinkle characteristics, thereby achieving a more effective smoothing effect. By selecting a reasonable adjustment smoothing method, the accuracy and efficiency of smoothing are improved, and production interruptions or defective products caused by improper smoothing are reduced, thereby improving the overall production efficiency and battery cell quality. The present invention determines the ripple trend parameters according to the first abnormal ripple and the characteristic abnormal ripple through the smoothing compensation module to determine the smoothing adjustment method for smoothing the pole ear. Furthermore, it realizes the adaptive adjustment of the smoothing parameters according to the comparison of the pole ear surface abnormalities before and after pre-smoothing, thereby improving the reliability of the pole ear smoothing system for battery cell winding.

[0020] In particular, the present invention determines through the smoothing compensation module that when the corrugation trend parameter meets the pulse smoothing condition, the smoothing adjustment method for smoothing the pole ear is to apply high-frequency pulse pressure to the smoothing roller, and determine the pulse frequency of the high-frequency pulse pressure based on the corrugation trend parameter. It can be understood that the corrugation trend parameter meets the pulse smoothing condition, that is, the corrugation trend parameter exceeds the preset corrugation trend parameter threshold, which indicates that the direction of the corrugations on the surface of the pole ear before pre-smoothing is less similar to the direction of the newly appeared corrugations on the surface of the pole ear after pre-smoothing, and the change in the corrugation direction is large. The traditional continuous pressure cannot effectively smooth the pole The surface of the tab is smoothed, and high-frequency pulse pressure can quickly apply multiple pressures to the tab, breaking the original stress distribution, promoting local plastic deformation of the tab material, and more efficiently eliminating wrinkles on the tab surface. Through more precise smoothing operations, defects such as internal short circuits and tab tears caused by tab surface abnormalities are reduced, the defective rate in the battery production process is reduced, and the overall quality and safety of the battery cell are improved. Furthermore, the smoothing parameters are adaptively adjusted according to the comparison of tab surface abnormalities before and after pre-smoothing, thereby improving the reliability of the tab smoothing system used for battery cell winding.

[0021] In particular, the present invention determines through the smoothing compensation module that when the ripple trend parameters do not meet the pulse smoothing conditions, the smoothing adjustment method for smoothing the tab is to adjust the angle between the smoothing roller and the tab, and determine the increase in the angle according to the ripple extension factor and the ripple distribution parameters of the second surface image. It can be understood that adjusting the angle between the smoothing roller and the tab can change the force direction and magnitude of the tab during the winding process, so that the stress distribution on the tab surface is more uniform. Determining the angle change based on the ripple extension factor and the ripple distribution parameters can make the adjustment of the smoothing roller more accurately target the wrinkle characteristics of the tab surface, improve the accuracy and effect of smoothing, and through more precise smoothing operations, reduce defects such as internal short circuits and tab tears in the battery caused by tab wrinkles, reduce the defective rate in the battery production process, and improve the overall quality and safety of the battery cell. Furthermore, it is achieved that the smoothing parameters are adaptively adjusted according to the comparison of the abnormalities on the tab surface before and after pre-smoothing, thereby improving the reliability of the tab smoothing system for battery cell winding. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a functional block diagram of a tab smoothing system for battery cell winding according to an embodiment of the present invention; Figure 2 This is a logic flow chart of the surface analysis module screening characteristic abnormal ripples according to an embodiment of the present invention; Figure 3 This is a logic flow chart of the surface analysis module determining whether pre-smoothing is effective according to an embodiment of the present invention; Figure 4 This is a logic flow chart of the smoothing compensation module in an embodiment of the present invention determining a smoothing adjustment method for smoothing the tab. DETAILED DESCRIPTION

[0023] In order to make the objects and advantages of the present invention more clearly understood, the present invention is further described below in conjunction with embodiments; it should be understood that the specific embodiments described herein are merely used to explain the present invention and are not intended to limit the present invention.

[0024] The preferred embodiments of the present invention are described below with reference to the accompanying drawings. It should be understood by those skilled in the art that these embodiments are only used to explain the technical principles of the present invention and are not intended to limit the scope of protection of the present invention.

[0025] It should be noted that, in the description of the present invention, terms such as "upper", "lower", "inside" and "outside" indicating directions or positional relationships are based on the directions or positional relationships shown in the accompanying drawings. This is only for the convenience of description and does not indicate or imply that the device or element must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it cannot be understood as a limitation on the present invention.

[0026] Furthermore, it should be noted that, in the description of the present invention, unless otherwise expressly specified or limited, the terms "mounted" and "connected" should be understood in a broad sense. For example, they may refer to fixed, detachable, or integral connections; mechanical or electrical connections; direct or indirect connections through an intermediate medium; or internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0027] See also Figure 1 As shown, it is a functional block diagram of a tab smoothing system for battery cell winding according to an embodiment of the present invention. A tab smoothing system for battery cell winding according to the present invention includes: a smoothing control module, comprising a first smoothing unit for pre-smoothing the tab, and a second smoothing unit for smoothing the tab; Specifically, the embodiment of the present invention does not specifically limit the structure of the first smoothing unit and the second smoothing unit. Preferably, they can be cylindrical smoothing rollers or bow-shaped smoothing rollers, consisting of a pair of smoothing rollers, which apply controllable pressure through a servo motor or the like to mechanically smooth the tabs. This will not be repeated.

[0028] a feature acquisition module connected to the smoothing control module, for acquiring a first surface image of the tab before pre-smoothing and a second surface image after pre-smoothing; Specifically, the embodiment of the present invention does not specifically limit the structure of the feature acquisition module. Preferably, it can be an industrial camera to obtain the surface images of the tab before and after pre-smoothing, which will not be repeated here.

[0029] Specifically, the acquisition frequency of the first surface image and the second surface image is determined according to the tab winding speed, so as to obtain the surface images of the same tab region before and after the pre-smoothing.

[0030] a pre-analysis module, connected to the smoothing control module and the feature acquisition module, respectively, for marking a first abnormal ripple based on the first surface image of the tab, and determining a pre-smoothing smoothing roller pressure parameter based on a ripple distribution parameter and a ripple extension parameter; Specifically, the embodiment of the present invention does not specifically limit the structure of the pre-analysis module. Preferably, it can be a processor used in a computer to mark the first abnormal ripple, determine the ripple distribution parameters and the ripple extension parameters, and determine the smoothing roller pressure parameters, and use the edge algorithm to identify abnormal ripples in the image. This will not be repeated.

[0031] a surface analysis module, connected to the feature acquisition module and the pre-analysis module, respectively, for marking a second abnormal ripple based on the second surface image of the tab, and screening characteristic abnormal ripples based on the first abnormal ripples and the second abnormal ripples to determine whether the pre-smoothing is effective; Specifically, the embodiment of the present invention does not specifically limit the structure of the surface analysis module. Preferably, it can be a microprocessor for screening characteristic abnormal ripples and determining whether pre-smoothing is effective. This will not be repeated.

[0032] A smoothing compensation module is respectively connected to the smoothing control module and the surface analysis module, and is used to determine the ripple trend parameters according to the first abnormal ripple and the characteristic abnormal ripple based on the judgment result that pre-smoothing is invalid, so as to determine that the smoothing adjustment method for smoothing the tab is to apply high-frequency pulse pressure to the smoothing roller, determine the pulse frequency of the high-frequency pulse pressure based on the ripple trend parameters, or adjust the angle between the smoothing roller and the tab, and determine the increase in the angle according to the ripple extension factor and the ripple distribution parameters of the second surface image.

[0033] Specifically, the embodiment of the present invention does not specifically limit the structure of the surface analysis module. Preferably, it can be composed of logic components, which can be microprocessors and processors used in computers, etc., to determine the ripple trend parameters and determine the smoothing adjustment method for smoothing the tabs. This will not be repeated.

[0034] Specifically, the pre-analysis module is used to determine the ripple distribution parameter and the ripple extension parameter, wherein: The pre-analysis module is used to calculate the distance between the midpoint of any first abnormal ripple and the midpoints of the other first abnormal ripples, and determine the variance of the distance as the ripple distribution parameter; The ripple extension parameter is an average value of the distances between the endpoints of each first abnormal ripple.

[0035] Specifically, the midpoint of the first abnormal ripple is the midpoint of the length of the first abnormal ripple between the characteristic endpoints. The midpoint is located on the first abnormal ripple. The interval distance between any endpoint on the first abnormal ripple and the remaining endpoints is calculated, and the endpoint with the maximum interval distance is determined as the characteristic endpoint.

[0036] Specifically, the distance between the midpoint of any first abnormal ripple and the midpoints of the remaining first abnormal ripples is the straight-line distance between the midpoint of any first abnormal ripple and the midpoints of the remaining first abnormal ripples.

[0037] Specifically, the pre-analysis module is used to determine the smoothing roller pressure parameters for pre-smoothing the tab, wherein: The pressure parameters of the smoothing roller for pre-smoothing the tab are respectively positively correlated with the corrugation distribution parameter and the corrugation extension parameter.

[0038] Specifically, the smoothing roller pressure parameter for pre-smoothing the tab is the product of the smoothing roller pressure parameter reference value and the smoothing roller pressure factor. The smoothing roller pressure factor is the distribution factor × corrugation distribution parameter / corrugation distribution parameter reference value + extension factor × corrugation extension parameter / corrugation extension parameter reference value. The smoothing roller pressure parameter reference value is the average value of the smoothing roller pressure parameter for smoothing the tab in the historical data. The corrugation distribution parameter reference value is the average value of the corrugation distribution parameter of the tab surface corrugations in the historical data. The corrugation extension parameter is the average value of the corrugation extension parameter of the tab surface corrugations in the historical data. The distribution factor and extension factor are set by those skilled in the art based on the degree of influence of the corrugation distribution parameter and the corrugation extension parameter in the historical data on the calculation results. The distribution factor + extension factor = 1. Preferably, the distribution factor can be 0.5 and the extension factor can be 0.5.

[0039] Specifically, the embodiment of the present invention determines the smoothing roller pressure parameters for pre-smoothing the tabs based on the corrugation distribution parameters and the corrugation extension parameters through a pre-analysis module. It can be understood that by determining the smoothing roller pressure parameters based on the corrugation distribution parameters and the corrugation extension parameters, dynamic and precise regulation of the smoothing roller pressure can be achieved. By quantifying the uniformity of the corrugation distribution and the length characteristics of the corrugations, the smoothing roller pressure parameters for pre-smoothing the tabs are adaptively adjusted to avoid the problems of insufficient pressure or excessive pressure caused by traditional experience-based parameter adjustment, thereby improving the consistency and efficiency of tab smoothing, adapting to the abnormal differences of different batches of tabs, reducing tab damage and equipment wear caused by improper pressure, and improving production yield and equipment service life. The embodiment of the present invention determines the smoothing roller pressure parameters for pre-smoothing the tabs based on the corrugation distribution parameters and the corrugation extension parameters through a pre-analysis module, thereby achieving adjustment of the pre-smoothing parameters according to the real-time abnormal characteristics of the tab surface, thereby improving the reliability of the tab smoothing system for battery cell winding.

[0040] Specifically, it can be understood that the pressure of the smoothing roller needs to overcome the unevenness of the tab to make it fit the winding requirements. The corrugation distribution parameter and the corrugation extension parameter respectively reflect the density and extension trend of the corrugations on the tab. The corrugation distribution parameter is the spatial discreteness of the corrugations on the tab surface. The larger the corrugation distribution parameter, the more significant the local stress concentration is, and the greater the pressure coverage is required to eliminate the stress difference. The corrugation extension parameter is the scale characteristic of the corrugations on the tab. The larger the corrugation extension parameter, the longer the stress release path inside the material, and the higher the pressure is required to break through the yield strength of the material to interrupt it. Stress chain, thereby eliminating long ripples. The larger the ripple distribution parameter, the more uneven the ripple distribution on the surface of the tab. The larger the ripple extension parameter, the longer the ripple extension on the surface of the tab. The greater the stress difference of the tab, the greater the pressure required to pre-smooth the tab in order to overcome the surface defects of the tab. The embodiment of the present invention determines the pressure parameters of the smoothing roller for pre-smoothing the tab based on the ripple distribution parameter and the ripple extension parameter through a pre-analysis module, thereby realizing the adjustment of the pre-smoothing parameters according to the real-time abnormal characteristics of the tab surface, thereby improving the reliability of the tab smoothing system for battery cell winding.

[0041] See also Figure 2 As shown, it is a logic flow chart of the surface analysis module screening characteristic abnormal ripples according to an embodiment of the present invention. The surface analysis module is used to screen the characteristic abnormal ripples, wherein: The surface analysis module selects the second abnormal ripple as a characteristic abnormal ripple based on a determination result that the first abnormal ripple and the second abnormal ripple meet the characteristic abnormal ripple condition; If the first abnormal ripple and the second abnormal ripple do not meet the characteristic abnormal ripple condition, the surface analysis module does not screen the second abnormal ripple; The characteristic abnormal ripple condition is that the second abnormal ripple does not exist in the first surface image.

[0042] See also Figure 3 As shown, it is a logic flow chart of the surface analysis module of an embodiment of the present invention for determining whether the pre-smoothing is effective. The surface analysis module is used to determine whether the pre-smoothing is effective, wherein: The surface analysis module determines that the pre-smoothing is invalid based on a determination result that the characteristic abnormal ripples meet a pre-smoothing invalidation condition; If the characteristic abnormal ripples do not meet the pre-smoothing invalidation condition, the surface analysis module determines that the pre-smoothing is valid; The pre-smoothing invalidation condition is that the area of the characteristic abnormal ripple exceeds a preset area threshold.

[0043] Specifically, the preset area threshold is the product of the area reference value and the area factor. The area reference value is the average value of the sum of the areas of abnormal ripples on the surface characteristics of the tab in historical data. The area factor can be set by technical personnel in this field according to the smoothing accuracy requirements of the tab smoothing system. The higher the accuracy requirement, the smaller the area factor. The value range of the area factor can be [1.1, 1.3]. Preferably, the area factor can be 1.2.

[0044] Specifically, the embodiment of the present invention uses a surface analysis module to screen characteristic abnormal ripples based on the first abnormal ripples and the second abnormal ripples to determine whether pre-smoothing is effective. It can be understood that by comparing the surface ripples of the tab before and after pre-smoothing, it is possible to identify whether new ripples appear after pre-smoothing, and to analyze the surface condition of the tab in more detail, thereby judging the effectiveness of the pre-smoothing operation, improving production efficiency, quickly determining the pre-smoothing effect, and adjusting the smoothing parameters in time to reduce production interruptions or defective products caused by improper smoothing, thereby improving overall production efficiency, promptly discovering and correcting problems in the smoothing process, and avoiding the scrapping of the tab due to ineffective smoothing, thereby reducing production costs. The embodiment of the present invention uses a surface analysis module to screen characteristic abnormal ripples based on the first abnormal ripples and the second abnormal ripples to determine whether pre-smoothing is effective. Furthermore, it realizes the determination of whether pre-smoothing is effective based on the comparison of the abnormalities on the tab surface before and after pre-smoothing, thereby improving the reliability of the tab smoothing system for battery cell winding.

[0045] Specifically, it can be understood that if characteristic abnormal ripples that do not appear in the first surface image appear after pre-smoothing, that is, the mechanical stress applied during the smoothing process fails to reasonably release the internal stress of the original material, but instead induces new stress concentration in other areas. For example, when the pressure direction of the smoothing roller is parallel to the direction of the original abnormal ripples, although some areas can be flattened, the stress release in the vertical direction is insufficient, which can easily lead to the generation of new abnormal ripples. The embodiment of the present invention screens the characteristic abnormal ripples based on the first abnormal ripples and the second abnormal ripples to determine whether the pre-smoothing is effective. Furthermore, it is realized that whether the pre-smoothing is effective is determined based on the comparison of the abnormalities on the tab surface before and after pre-smoothing, thereby improving the reliability of the tab smoothing system for battery cell winding.

[0046] Specifically, the smoothing compensation module is used to determine a first ripple trend vector and a characteristic ripple trend vector, wherein: The smoothing compensation module uses any endpoint of the first abnormal ripple as a vector starting point, calculates the interval distances between the remaining endpoints on the first abnormal ripple and the endpoint, constructs a first ripple vector with the endpoint with the maximum interval distance as the vector end point, and determines the vector obtained by adding the first ripple vectors as the first ripple trend vector; Taking any endpoint of the characteristic abnormal ripple as the starting point of the vector, calculate the interval distance between the remaining endpoints on the characteristic abnormal ripple and the endpoint, and construct a characteristic ripple vector with the endpoint with the maximum interval distance as the vector end point. The vector obtained by adding up the characteristic ripple vectors is determined as the characteristic ripple trend vector.

[0047] Specifically, the endpoint serving as the starting point of the vector and the endpoint serving as the ending point of the vector are distributed along the moving direction of the tab.

[0048] Specifically, the smoothing compensation module is used to determine the ripple trend parameter, wherein: The smoothing compensation module calculates a vector angle between the first ripple trend vector and the characteristic ripple trend vector, and determines the vector angle as a ripple trend parameter.

[0049] See also Figure 4 As shown, it is a logic flow chart of the smoothing compensation module of an embodiment of the present invention for determining the smoothing adjustment method for smoothing the tab. The smoothing compensation module is used to determine the smoothing adjustment method for smoothing the tab, wherein: If the ripple trend parameter meets the determination result of the pulse smoothing condition, the smoothing compensation module determines that the smoothing adjustment method for smoothing the tab is to apply high-frequency pulse pressure to the smoothing roller, and determines the pulse frequency of the high-frequency pulse pressure based on the ripple trend parameter; Specifically, high-frequency pulse pressure is applied to the smoothing roller, and square wave pulses can be used to more effectively break the stress concentration of the tab material. The pressure amplitude range can be set according to the tab material. The pressure amplitude range of the aluminum foil tab can be 1~3MPa. Preferably, the pressure amplitude of the aluminum foil tab can be 2MPa. The pressure amplitude range of the copper foil tab can be 2~4MPa. Preferably, the pressure amplitude of the copper foil tab can be 3MPa. The pulse width can be in the range of 5~10ms to avoid overheating and deformation of the tab due to excessive pulse width. Preferably, the pulse width can be 7ms.

[0050] If the ripple trend parameter does not meet the determination result of the pulse smoothing condition, the smoothing compensation module determines that the smoothing adjustment method for smoothing the tab is to adjust the angle between the smoothing roller and the tab, and determines the increase amount of the angle according to the ripple extension factor and the ripple distribution parameter of the second surface image; Specifically, a servo motor can be used to drive a worm gear reducer, and a ball screw pair can be used to adjust the angle of the smoothing roller.

[0051] Specifically, the distance between the midpoint of any second abnormal ripple in the second surface image and the midpoints of the remaining second abnormal ripples is calculated, and the variance of the distance is determined as the ripple distribution parameter of the second surface image.

[0052] The pulse smoothing condition is that the ripple trend parameter exceeds a preset ripple trend parameter threshold.

[0053] Specifically, the preset ripple trend parameter threshold is the product of the ripple trend parameter reference value and the ripple trend factor. The ripple trend parameter reference value is the average value of the ripple trend parameter of the tab in historical data. The ripple trend factor can be set by technical personnel in this field according to the smoothing accuracy requirements of the tab smoothing system. The higher the accuracy requirement, the smaller the ripple trend factor. The value range of the ripple trend factor can be [1.1, 1.25]. Preferably, the ripple trend factor can be 1.2.

[0054] Specifically, the embodiment of the present invention determines the ripple trend parameters according to the first abnormal ripple and the characteristic abnormal ripple through the smoothing compensation module to determine the smoothing adjustment method for smoothing the tab. It can be understood that by constructing the ripple trend vector and calculating the vector angle, the change in the direction of the tab wrinkles before and after pre-smoothing can be quantified, providing a reliable basis for selecting a suitable smoothing strategy. Two different smoothing adjustment methods are determined according to whether the ripple trend parameters meet the pulse smoothing conditions. The targeted strategy can better adapt to different types of wrinkle characteristics, thereby achieving a more effective smoothing effect. By selecting a reasonable adjustment smoothing method, the accuracy and efficiency of smoothing are improved, and production interruptions or defective products caused by improper smoothing are reduced, thereby improving the overall production efficiency and battery cell quality. The embodiment of the present invention determines the ripple trend parameters according to the first abnormal ripple and the characteristic abnormal ripple through the smoothing compensation module to determine the smoothing adjustment method for smoothing the tab. Furthermore, the smoothing parameters are adaptively adjusted according to the comparison of the tab surface abnormalities before and after pre-smoothing, thereby improving the reliability of the tab smoothing system for battery cell winding.

[0055] Specifically, the smoothing compensation module is used to determine the pulse frequency of the high-frequency pulse pressure, wherein the pulse frequency is positively correlated with the ripple trend parameter.

[0056] Specifically, the adjustment amount of the pulse frequency is the product of the pulse frequency reference value and the frequency factor, the frequency factor is the trend coefficient × the ripple trend parameter / the ripple trend parameter reference value, the ripple trend parameter reference value is the average value of the ripple trend parameter of the pole ear in the historical data, the trend coefficient can be set by a technician in this field based on the average value of the historical data, the value range of the trend coefficient can be [0.1, 0.3] to avoid the pulse frequency adjustment being too large or too small, preferably, the trend coefficient can be 0.2.

[0057] Specifically, the embodiment of the present invention determines through the smoothing compensation module that when the ripple trend parameter meets the pulse smoothing condition, the smoothing adjustment method for smoothing the tab is to apply high-frequency pulse pressure to the smoothing roller, and determine the pulse frequency of the high-frequency pulse pressure based on the ripple trend parameter. It can be understood that the ripple trend parameter meets the pulse smoothing condition, that is, the ripple trend parameter exceeds the preset ripple trend parameter threshold, which indicates that the direction of the ripples on the surface of the tab before pre-smoothing is less similar to the direction of the newly appeared ripples on the surface of the tab after pre-smoothing, and the change in the ripple direction is large, and the traditional continuous pressure cannot be used. The high-frequency pulse pressure can effectively smooth the surface of the tab, and can quickly apply multiple pressures to the tab, breaking the original stress distribution, promoting local plastic deformation of the tab material, and more efficiently eliminating wrinkles on the tab surface. Through more precise smoothing operations, it can reduce defects such as internal short circuits and tab tears in the battery caused by tab surface abnormalities, reduce the defective rate in the battery production process, and improve the overall quality and safety of the battery cell. Furthermore, it can realize the adaptive adjustment of smoothing parameters according to the comparison of tab surface abnormalities before and after pre-smoothing, thereby improving the reliability of the tab smoothing system used for battery cell winding.

[0058] Specifically, it can be understood that the ripple trend parameter characterizes the degree of change in the direction of the ripples on the surface of the tab before and after pre-smoothing. When the ripple trend parameter is large, that is, the consistency of the direction of the ripples on the surface of the tab before and after pre-smoothing is poor, the direction of the ripples on the surface of the tab has changed significantly, and the stress distribution in different areas of the tab is quite different. The traditional continuous pressure smoothing method is difficult to effectively act on all wrinkle areas. The use of high-frequency pulse pressure can quickly change the stress distribution of the tab. Through the high-frequency vibration of the pulse pressure, the tab material undergoes multiple tiny plastic deformations in the local area, thereby more effectively eliminating wrinkles. The larger the ripple trend parameter, the worse the consistency of the ripple direction, and the more a higher frequency pulse pressure is needed to quickly adjust the stress distribution. The high pulse frequency can apply pressure multiple times in a short period of time, which can more effectively eliminate the ripples on the surface of the tab. Furthermore, the smoothing parameters are adaptively adjusted according to the abnormal comparison of the tab surface before and after pre-smoothing, thereby improving the reliability of the tab smoothing system used for battery cell winding.

[0059] Specifically, the smoothing compensation module is used to determine the increase in the angle between the smoothing roller and the tab. The increase in the angle is positively correlated with the corrugation distribution parameter and the corrugation extension factor, respectively. The smoothing compensation module is used to determine the component vector of the characteristic corrugation vector in the direction parallel to the length of the tab as the first component vector, determine the component vector of the characteristic corrugation vector in the direction perpendicular to the length of the tab as the second component vector, calculate the ratio of the modulus of the first component vector to the modulus of the second component vector, and determine the average value of the ratio as the corrugation extension factor.

[0060] Specifically, the initial angle between the smoothing roller and the tab can be 0°, that is, the smoothing roller is parallel to the plane where the tab is located.

[0061] Specifically, the increase in the angle is 360°×angle coefficient, the angle coefficient is distribution weight factor×corrugation distribution parameter / corrugation distribution parameter reference value+extension weight factor×corrugation extension factor / corrugation extension factor reference value, the corrugation distribution parameter reference value is the average value of the corrugation distribution parameters of the corrugations on the surface of the tab in the historical data, the corrugation extension factor reference value is the average value of the corrugation extension factors of the corrugations on the surface of the tab in the historical data, the distribution weight factor and the extension weight factor are set by those skilled in the art based on the degree of influence of the corrugation distribution parameters and the corrugation extension factors in the historical data on the calculation results, the distribution weight factor+extension weight factor=1, preferably, the distribution weight factor can be 0.5, and the extension weight factor can be 0.5.

[0062] Specifically, in an embodiment of the present invention, when the smoothing compensation module determines that the ripple trend parameters do not meet the pulse smoothing conditions, the smoothing adjustment method for smoothing the tab is to adjust the angle between the smoothing roller and the tab, and determine the increase in the angle according to the ripple extension factor and the ripple distribution parameters of the second surface image. It can be understood that adjusting the angle between the smoothing roller and the tab can change the force direction and magnitude of the tab during the winding process, so that the stress distribution on the tab surface is more uniform. Determining the angle change based on the ripple extension factor and the ripple distribution parameters can make the adjustment of the smoothing roller more accurately target the wrinkle characteristics of the tab surface, improve the accuracy and effect of smoothing, and through more precise smoothing operations, reduce defects such as internal short circuits and tab tears in the battery caused by tab wrinkles, reduce the defective rate in the battery production process, and improve the overall quality and safety of the battery cell. Furthermore, it is achieved that the smoothing parameters are adaptively adjusted according to the comparison of the abnormalities on the tab surface before and after pre-smoothing, thereby improving the reliability of the tab smoothing system for battery cell winding.

[0063] Specifically, it can be understood that adjusting the angle between the smoothing roller and the tab can change the direction and magnitude of the force on the tab during the winding process, making the stress distribution on the tab surface more uniform and achieving a better smoothing effect. The ripple distribution parameter characterizes the density and distribution uniformity of the ripples on the tab surface. The larger the ripple distribution parameter, the more uneven the ripple distribution, the greater the difference in flatness of the tab surface, the more stress concentration areas exist, and the larger the angle required to change the force distribution of the smoothing roller on the tab, thereby more effectively smoothing the wrinkles. The ripple extension factor characterizes the extension ratio of the ripples in the length direction and the vertical direction of the tab. When the ripple extension factor is larger, the extension of the ripples in the length direction is more significant, the larger the angle between the smoothing roller and the tab, and the better the smoothing roller can smooth the ripples on the tab surface. Furthermore, the smoothing parameters are adaptively adjusted according to the comparison of the abnormalities on the tab surface before and after pre-smoothing, thereby improving the reliability of the tab smoothing system for battery cell winding.

[0064] Thus far, the technical solutions of the present invention have been described in conjunction with the preferred embodiments shown in the accompanying drawings. However, it will be readily understood by those skilled in the art that the scope of protection of the present invention is obviously not limited to these specific embodiments. Without departing from the principles of the present invention, those skilled in the art may make equivalent changes or substitutions to the relevant technical features, and the technical solutions after such changes or substitutions will fall within the scope of protection of the present invention.

[0065] The foregoing description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that the present invention is susceptible to various modifications and variations. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. A tab smoothing system for battery cell winding, characterized in that: include: a smoothing control module, comprising a first smoothing unit for pre-smoothing the tab, and a second smoothing unit for smoothing the tab; a feature acquisition module connected to the smoothing control module, for acquiring a first surface image of the tab before pre-smoothing and a second surface image after pre-smoothing; a pre-analysis module, connected to the smoothing control module and the feature acquisition module, respectively, for marking a first abnormal ripple based on the first surface image of the tab, and determining a pre-smoothing smoothing roller pressure parameter based on a ripple distribution parameter and a ripple extension parameter; a surface analysis module, connected to the feature acquisition module and the pre-analysis module, respectively, for marking a second abnormal ripple based on the second surface image of the tab, and screening characteristic abnormal ripples based on the first abnormal ripples and the second abnormal ripples to determine whether the pre-smoothing is effective; A smoothing compensation module is respectively connected to the smoothing control module and the surface analysis module, and is used to determine the ripple trend parameters according to the first abnormal ripple and the characteristic abnormal ripple based on the judgment result that pre-smoothing is invalid, so as to determine that the smoothing adjustment method for smoothing the tab is to apply high-frequency pulse pressure to the smoothing roller, determine the pulse frequency of the high-frequency pulse pressure based on the ripple trend parameters, or adjust the angle between the smoothing roller and the tab, and determine the increase in the angle according to the ripple extension factor and the ripple distribution parameters of the second surface image.

2. The tab smoothing system for battery cell winding according to claim 1, characterized in that: The pre-analysis module is used to determine the ripple distribution parameter and the ripple extension parameter, wherein: The pre-analysis module is used to calculate the distance between the midpoint of any first abnormal ripple and the midpoints of the other first abnormal ripples, and determine the variance of the distance as the ripple distribution parameter; The ripple extension parameter is an average value of the distances between the endpoints of each first abnormal ripple.

3. The tab smoothing system for battery cell winding according to claim 2, characterized in that: The pre-analysis module is used to determine the smoothing roller pressure parameters for pre-smoothing the tab, wherein: The pressure parameters of the smoothing roller for pre-smoothing the tab are respectively positively correlated with the corrugation distribution parameter and the corrugation extension parameter.

4. The tab smoothing system for battery cell winding according to claim 3, characterized in that: The surface analysis module is used to screen the characteristic abnormal ripples, wherein: The surface analysis module selects the second abnormal ripple as a characteristic abnormal ripple based on a determination result that the first abnormal ripple and the second abnormal ripple meet the characteristic abnormal ripple condition; The characteristic abnormal ripple condition is that the second abnormal ripple does not exist in the first surface image.

5. The tab smoothing system for battery cell winding according to claim 4, characterized in that: The surface analysis module is used to determine whether the pre-smoothing is effective, wherein: The surface analysis module determines that the pre-smoothing is invalid based on a determination result that the characteristic abnormal ripples meet a pre-smoothing invalidation condition; The pre-smoothing invalidation condition is that the area of the characteristic abnormal ripple exceeds a preset area threshold.

6. The tab smoothing system for battery cell winding according to claim 5, characterized in that: The smoothing compensation module is used to determine the first ripple trend vector and the characteristic ripple trend vector, wherein: The smoothing compensation module uses any endpoint of the first abnormal ripple as a vector starting point, calculates the interval distances between the remaining endpoints on the first abnormal ripple and the endpoint, constructs a first ripple vector with the endpoint with the maximum interval distance as the vector end point, and determines the vector obtained by adding the first ripple vectors as the first ripple trend vector; Taking any endpoint of the characteristic abnormal ripple as the starting point of the vector, calculate the interval distance between the remaining endpoints on the characteristic abnormal ripple and the endpoint, and construct a characteristic ripple vector with the endpoint with the maximum interval distance as the vector end point. The vector obtained by adding up the characteristic ripple vectors is determined as the characteristic ripple trend vector.

7. The tab smoothing system for battery cell winding according to claim 6, characterized in that: The smoothing compensation module is used to determine the ripple trend parameter, wherein: The smoothing compensation module calculates a vector angle between the first ripple trend vector and the characteristic ripple trend vector, and determines the vector angle as a ripple trend parameter.

8. The tab smoothing system for battery cell winding according to claim 7, characterized in that: The smoothing compensation module is used to determine a smoothing adjustment method for smoothing the tab, wherein: If the ripple trend parameter meets the determination result of the pulse smoothing condition, the smoothing compensation module determines that the smoothing adjustment method for smoothing the tab is to apply high-frequency pulse pressure to the smoothing roller, and determines the pulse frequency of the high-frequency pulse pressure based on the ripple trend parameter; If the ripple trend parameter does not meet the determination result of the pulse smoothing condition, the smoothing compensation module determines that the smoothing adjustment method for smoothing the tab is to adjust the angle between the smoothing roller and the tab, and determines the increase amount of the angle according to the ripple extension factor and the ripple distribution parameter of the second surface image; The pulse smoothing condition is that the ripple trend parameter exceeds a preset ripple trend parameter threshold.

9. The tab smoothing system for battery cell winding according to claim 8, characterized in that: The smoothing compensation module is used to determine the pulse frequency of the high-frequency pulse pressure, wherein the pulse frequency is positively correlated with the ripple trend parameter.

10. The tab smoothing system for battery cell winding according to claim 9, characterized in that: The smoothing compensation module is used to determine the increase in the angle between the smoothing roller and the tab. The increase in the angle is positively correlated with the corrugation distribution parameter and the corrugation extension factor, respectively. The smoothing compensation module is used to determine the component vector of the characteristic corrugation vector in the direction parallel to the length of the tab as the first component vector, determine the component vector of the characteristic corrugation vector in the direction perpendicular to the length of the tab as the second component vector, calculate the ratio of the modulus of the first component vector to the modulus of the second component vector, and determine the average value of the ratio as the corrugation extension factor.

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