An electrode tab flattening device for an electric battery

Abstract

The utility model provides a kind of electric core tab flattening device, including pre-flattening mechanism and main flattening mechanism;The pre-flattening mechanism is used to carry out pre-flattening treatment to the tab, by the pressure applied to the tab makes the tab further fold towards the electric core axis, so that the included angle between the tab and the electric core main body end face is reduced from alpha to beta, wherein beta < alpha;The main flattening mechanism is used to carry out final flattening treatment to the tab after pre-flattening treatment, by the pressure applied to the tab makes the tab further fold towards the electric core axis, so that the included angle between the tab and the electric core main body end face is reduced from beta to 0 °, and make all tabs between each end face stack and compress tightly, reach predetermined thickness and flatness;By increasing pre-flattening process before flattening process, each layer of tab of multi-tab cylindrical electric core can be fully flattened, battery quality and safety can be improved.

Description

Technical Field

[0001] This utility model relates to the field of battery production technology, and in particular to a battery cell tab flattening device. Background Technology

[0002] In recent years, lithium-ion batteries have been widely used due to their unique high energy density, long cycle life, and good safety. Especially against the backdrop of the rapid development of the new energy vehicle market, the development of the power battery industry has accelerated further. With continuous technological innovation, large cylindrical batteries (such as the 4690 large cylindrical battery) have significantly reduced internal resistance and heat generation rate thanks to breakthroughs in multi-tab technology, effectively solving the heat dissipation problem of high-energy-density cells. Their advantages, such as high capacity, long driving range, efficient charging capability, and low cost, have enabled them to occupy an important position in the power battery market, and their market share continues to rise.

[0003] As a key component of multi-tab cylindrical batteries, the multi-tab cylindrical cell employs a multi-miniaturized tab design. Compared to the traditional single, larger tab design, this design significantly reduces internal resistance, improves current distribution, increases charge and discharge efficiency, and optimizes heat dissipation. Furthermore, the multi-tab design provides better conditions for subsequent welding processes, ensuring the reliability of electrical connections and mechanical stability.

[0004] In the manufacturing process of multi-tab cylindrical battery cells, in order to achieve orderly stacking of the tabs on the end face of the cell after winding, the tabs are usually pre-folded before winding, that is, a certain bending angle is applied to the tabs, and then during the winding process, the tabs are stacked layer by layer towards the cell axis in a specific order. For example Figure 1 The diagram shows the state of a multi-tab cylindrical battery cell after winding and before flattening. At this time, the tabs are not pressed and flattened on the end face of the battery cell, and the angle between the tabs and the end face of the battery cell is α.

[0005] To meet the requirements of subsequent welding and assembly processes for electrical connection quality and mechanical stability, a cell tab flattening device is typically used to flatten the cell tabs. For example... Figure 2 The diagram shows the state of a multi-tab cylindrical battery cell after the tabs are flattened. Flattening the tabs means applying appropriate pressure to make all the tabs bend further toward the battery cell axis. At this time, the angle between the tabs and the end face of the battery cell is 0°, and the angle with the side of the battery cell is 90°. All the tabs are stacked and pressed together to achieve the predetermined thickness and flatness.

[0006] However, current battery cell tab flattening devices typically only perform one flattening process when flattening tabs on multi-tab cylindrical cells, which cannot meet the different compaction requirements of multi-layer tabs. Specifically, the outermost tabs may "explode," while the middle layer tabs may not be compacted properly, resulting in gaps between the tabs. These defects allow electrolyte to easily seep into the gaps during electrolyte injection, increasing the risk of short circuits or performance degradation. These problems not only affect the overall quality and safety of the battery but also limit its potential for large-scale commercial application. Utility Model Content

[0007] This invention provides a cell tab flattening device that adds a pre-flattening process before the flattening process, ensuring that each layer of tabs in a multi-tab cylindrical cell is fully compressed and flattened, thereby improving battery quality and safety. The specific solution is as follows:

[0008] A battery cell tab flattening device is used for flattening the tabs of a battery cell. The battery cell is a multi-tab cylindrical battery cell, including a battery cell body and multiple tabs. The tabs extend from the end faces of both ends of the battery cell body, bend towards the battery cell axis and are stacked. The included angle between each tab and the end face of the battery cell body is α, where α < 90°. The device includes a pre-flattening mechanism and a main flattening mechanism.

[0009] The pre-flattening mechanism is used to pre-flatten the tab. By applying pressure to the tab, the tab is further bent toward the cell axis, so that the angle between the tab and the end face of the cell body is reduced from α to β, where β < α.

[0010] The main flattening mechanism is used to perform the final flattening process on the pre-flattened tabs. By applying pressure to the tabs, the tabs are further bent toward the axis of the battery cell, so that the angle between the tabs and the end face of the battery cell body is reduced from β to 0°, and all the tabs on each end face are stacked and pressed together to achieve a predetermined thickness and flatness.

[0011] Furthermore, the pre-flattening mechanism includes a first pre-flattening component and a second pre-flattening component;

[0012] The first pre-flattening assembly is used to perform an initial pre-flattening process on the electrode tab. By applying pressure to the electrode tab, the electrode tab is further bent toward the axis of the battery cell, so that the angle between the electrode tab and the end face of the battery cell body is reduced from α to γ, where γ < α.

[0013] The second pre-flattening assembly is used to perform a second pre-flattening process on the tab after the initial pre-flattening process. By applying pressure to the tab, the tab is further bent toward the cell axis, so that the angle between the tab and the end face of the cell body is further reduced from γ to β, where β < γ.

[0014] Furthermore, α = 70°, γ = 45°, and β = 30°.

[0015] Furthermore, it also includes a transmission mechanism, which can be used to realize the transmission of the battery cell, so that the battery cell can move stably between different workstations.

[0016] Further, the first pre-flattening assembly includes first pre-flattening units respectively disposed at both ends of the battery cell. The first pre-flattening unit includes a first pre-flattening fixture and a first pre-flattening drive component. The first pre-flattening fixture is provided with a first closing groove adapted to the battery cell at one end near the battery cell. The first closing groove includes a first pre-flattening plane, a first closing cone surface, and a first extended cone surface. The first pre-flattening plane is located at the bottom of the first closing groove and is opposite to the end face of the battery cell body. The first closing cone surface is an annular cone surface extending from the edge of the first pre-flattening plane, and the angle between the first closing cone surface and the first pre-flattening plane is 180°-γ. The first extended cone surface is a trumpet-shaped annular cone surface extending from the edge of the first closing cone surface. The first pre-flattening drive component can be used to drive the first pre-flattening fixture to move closer to or away from the battery cell along the axial direction of the battery cell.

[0017] Further, the second pre-flattening assembly includes a cell positioning assembly and second pre-flattening units respectively disposed at both ends of the cell. The second pre-flattening unit includes a second pre-flattening fixture and a second pre-flattening drive component. The second pre-flattening fixture has a second closing groove adapted to the cell at one end near the cell. The second closing groove includes a second pre-flattening plane and a second closing conical surface. The second pre-flattening plane is located at the bottom of the second closing groove and is opposite to the end face of the cell body. The second closing conical surface is an annular conical surface extending from the edge of the second pre-flattening plane, and the angle between the second closing conical surface and the second pre-flattening plane is 180°-β. The cell positioning assembly can be used to fix the cell body. The second pre-flattening drive component can be used to drive the second pre-flattening fixture to move closer to or away from the cell along the cell axis.

[0018] Furthermore, the main flattening mechanism includes a cell positioning assembly and main flattening units respectively disposed at both ends of the cell. The main flattening unit includes a main flattening fixture and a main flattening drive component. The main flattening fixture has a flattening groove adapted to the cell at one end near the cell. The flattening groove includes a flattening end face and a closing side face. The flattening end face is located at the bottom of the flattening groove and is opposite to the end face of the cell body. The closing side face is an annular surface extending from the edge of the flattening end face, and the angle between the closing side face and the flattening end face is 90°. The cell positioning assembly can be used to fix the cell body. The main flattening drive component can be used to drive the main flattening fixture to move closer to or away from the cell along the cell axis.

[0019] Furthermore, the battery cell positioning assembly includes a positioning gripper, a gripper opening and closing cylinder, and a gripper lifting cylinder; the gripper opening and closing cylinder can drive the positioning gripper to open and close; the gripper lifting cylinder can drive the positioning gripper to move up and down; the positioning gripper is adapted to the side of the battery cell body and can clamp the battery cell body by contacting the side of the battery cell body.

[0020] Furthermore, the main flattening drive component is a servo motor, and the main flattening drive component drives the main flattening fixture to reach the set flattening position, stays for 1-2 seconds, and then returns to the original position.

[0021] Furthermore, an anti-clogging center pin is provided on the flattened end face, and the anti-clogging center pin is adapted to the liquid injection hole on the end face of the battery cell body and can be inserted into the liquid injection hole.

[0022] The battery cell tab flattening device provided by this utility model pre-flattens the tabs through the pre-flattening mechanism, and then performs the final flattening process on the pre-flattened tabs through the main flattening mechanism. Compared with the prior art which only sets one flattening process, this device can ensure that each layer of tabs is fully flattened and compacted. This reduces the occurrence of phenomena such as the outermost tabs bursting, the middle layer tabs not being compacted, and gaps between tabs. In turn, it reduces the risk of electrolyte seeping into the gaps between the tabs, causing short circuits or performance degradation in the battery, and improves battery quality and safety.

[0023] In some embodiments, the pre-flattening mechanism includes a first pre-flattening component and a second pre-flattening component. During the pre-flattening process of the tab, the tab is pre-flattened twice by the first pre-flattening component and the second pre-flattening component, gradually reducing the angle between the tab and the end face of the cell body from the initial angle α to the intermediate angle γ, and then further reducing it to the final preset angle β, where α>γ>β. This multi-stage progressive flattening method can effectively alleviate the stress concentration of the tab material during bending, prevent the tab from breaking or generating debris, and improve the bonding consistency and process stability after flattening, thereby significantly improving the assembly yield and subsequent welding accuracy of the cell.

[0024] In some embodiments, when the initial included angle α between the tab and the end face of the cell body is 70°, tests show that when the initial pre-flattening treatment amplitude is 25° and the secondary pre-flattening treatment amplitude is 15° (i.e., γ = 45° after the initial pre-flattening treatment and β = 30° after the secondary pre-flattening treatment), the flattening and pressing effect of the tab is better, which is beneficial to improving the production quality of the cell.

[0025] In some embodiments, the battery cell tab flattening device further includes a transmission mechanism, which enables the battery cell to move stably between different workstations, thereby improving the production efficiency of the battery cell.

[0026] In some embodiments, the first pre-flattening assembly includes first pre-flattening units respectively disposed at both ends of the battery cell. The first pre-flattening unit includes a first pre-flattening fixture and a first pre-flattening drive component. Under the drive of the first pre-flattening drive component, the first pre-flattening fixtures located at both ends of the battery cell approach the battery cell along the axial direction of the battery cell. The first extended conical surface in the first pre-flattening fixture can better guide the tab into a predetermined position, thereby achieving the positioning of the tab. The first tapered conical surface can tighten the tab on the outer ring of the battery cell, and the first pre-flattening plane can apply pressure to the tab, flattening and tightening it, thereby causing the tab to bend further toward the axis of the battery cell, reducing the angle between the tab and the end face of the battery cell body from α to γ. This not only has a simple structure but also a good flattening effect.

[0027] In some embodiments, the second pre-flattening assembly includes a cell positioning assembly and second pre-flattening units respectively disposed at both ends of the cell; wherein, the second pre-flattening unit includes a second pre-flattening fixture and a second pre-flattening drive component; firstly, the cell body is fixed by the cell positioning assembly to achieve precise positioning of the cell; then, driven by the second pre-flattening drive component, the second pre-flattening fixtures located at both ends of the cell approach the cell along the cell axis; the second tapered surface in the second pre-flattening fixture can tighten the tabs on the outer ring of the cell, and the second pre-flattening plane can apply pressure to the tabs, flattening and tightening them, thereby causing the tabs to bend further toward the cell axis, reducing the angle between the tabs and the end face of the cell body from γ to β, which not only has a simple structure but also a good flattening effect.

[0028] In some embodiments, the main flattening mechanism includes a cell positioning assembly and main flattening units respectively disposed at both ends of the cell; wherein, the main flattening unit includes a main flattening fixture and a main flattening drive component; firstly, the cell body is fixed by the cell positioning assembly to achieve precise positioning of the cell; then, driven by the main flattening drive component, the main flattening fixtures located at both ends of the cell approach the cell along the cell axis; the constricting side of the main flattening fixture can tighten the tabs on the outer ring of the cell, and the flattening end face can apply pressure to the tabs for final flattening and pressing, thereby causing the tabs to bend further toward the cell axis, reducing the angle between the tabs and the end face of the cell body from β to 0°, and stacking and pressing all the tabs on each end face to achieve a predetermined thickness and flatness, which is not only simple in structure but also has a good flattening effect.

[0029] In some embodiments, the battery cell positioning assembly includes a positioning gripper, a gripper opening and closing cylinder, and a gripper lifting cylinder. Through the cooperation between the positioning gripper and the gripper opening and closing cylinder, the battery cell can be stably and reliably clamped, achieving precise positioning of the battery cell. By driving the positioning gripper to move up and down through the gripper lifting cylinder, interference caused by the positioning gripper when not in operation can be avoided, making the battery cell tab flattening device more flexible.

[0030] In some embodiments, the main flattening drive component is a servo motor, and the main flattening drive component drives the main flattening fixture to reach the set flattening position, stays for 1-2 seconds, and then returns to the original position. Firstly, the servo motor is selected as the main flattening drive component, which can accurately control the movement trajectory and termination position of the main flattening fixture, resulting in higher precision, faster response, and better stability. When the main flattening fixture reaches the set flattening position, the servo motor controls it to stay for 1-2 seconds before resetting, which allows the tabs to fit more fully against the end face of the battery cell body under pressure, reducing springback or warping, improving flattening consistency and process stability, and enhancing production quality.

[0031] In some embodiments, an anti-clogging center pin is provided on the flattening end face, which can not only prevent the electrode tab from entering the injection hole and causing blockage during the flattening process, but also play a guiding and positioning role, ensuring that the material entering the flattening groove each time is accurately in the optimal flattening position, thereby improving the consistency and quality of processing. Attached Figure Description

[0032] Figure 1 This is a schematic diagram of the state of a multi-tab cylindrical battery cell after winding and before flattening.

[0033] Figure 2 This is a schematic diagram showing the state of a multi-tab cylindrical battery cell after the tabs have been flattened.

[0034] Figure 3 This is a schematic diagram of the battery cell tab flattening device.

[0035] Figure 4 This is a schematic diagram of the structure of the first pre-flattening component.

[0036] Figure 5 This is a schematic diagram of the first closing groove.

[0037] Figure 6 Schematic diagram of the second pre-flattening component Figure 1 .

[0038] Figure 7 Schematic diagram of the second pre-flattening component Figure 2 .

[0039] Figure 8 This is a schematic diagram of the second closing groove.

[0040] Figure 9 Schematic diagram of the main flattening mechanism Figure 1 .

[0041] Figure 10 Schematic diagram of the main flattening mechanism Figure 2 .

[0042] Figure 11 This is a schematic diagram of the flattening groove.

[0043] The reference numerals in the attached figures are as follows: 1 is the battery cell, 11 is the battery cell body, 12 is the electrode tab, 2 is the pre-flattening mechanism, 21 is the first pre-flattening assembly, 211 is the first pre-flattening fixture, 2111 is the first closing groove, 21111 is the first pre-flattening plane, 21112 is the first closing conical surface, 21113 is the first extended conical surface, 212 is the first pre-flattening drive component, 22 is the second pre-flattening assembly, 221 is the second pre-flattening fixture, and 2211 is the second closing groove. 22111 is the second pre-pressing plane, 22112 is the second conical surface, 222 is the second pre-pressing flattening drive component, 3 is the main flattening mechanism, 31 is the main flattening fixture, 311 is the flattening groove, 3111 is the flattening end face, 3112 is the constriction side, 3113 is the anti-blocking center pin, 32 is the main flattening drive component, 4 is the transmission mechanism, 5 is the cell positioning component, 51 is the positioning gripper, 52 is the gripper opening and closing cylinder, and 53 is the gripper lifting cylinder. Detailed Implementation

[0044] The specific embodiments of this utility model will be further described below with reference to the accompanying drawings. For ease of explanation, the terms "front," "rear," "positive," "negative," "left," "right," "top," "bottom," "upper," "lower," "inner," "outer," and "inner" in this utility model indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or component referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model or limitations on the actual orientation of the product or device during production, use, sales, etc. In addition, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Furthermore, in the embodiments of this utility model, unless otherwise explicitly specified and limited, the terms "installation," "setting," "connection," "fixing," and "composition," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0045] This utility model provides a battery cell tab flattening device, which can be used for flattening the tabs of a battery cell 1. In this embodiment, the battery cell 1 is a multi-tab cylindrical battery cell, including a battery cell body 11 and multiple tabs 12, such as... Figure 1The diagram shows the state of a multi-tab cylindrical battery cell after winding and before flattening. The tabs 12 extend from both ends of the battery cell body 11, bend towards the axis of the battery cell 1, and are stacked. The angle between each tab 12 and the end face of the battery cell body 11 is α, where α < 90°. Figure 2 The diagram shows the state of the multi-tab cylindrical battery cell after the tabs are flattened. In this embodiment, flattening the tabs means applying appropriate pressure to make the tabs 12 bend further toward the axis of the battery cell 1, so that the angle between the tabs 12 and the end face of the battery cell body 11 is 0° and the angle with the side face of the battery cell body 11 is 90°, and all the tabs 12 on each end face are stacked and pressed together to achieve a predetermined thickness and flatness.

[0046] like Figure 3 The diagram shows the structure of the battery cell tab flattening device. Specifically, the battery cell tab flattening device includes a pre-flattening mechanism 2 and a main flattening mechanism 3, wherein:

[0047] The pre-flattening mechanism 2 is used to pre-flatten the tab 12, that is, by applying pressure to the tab 12, the tab 12 is further bent toward the axis of the cell 1, thereby reducing the angle between the tab 12 and the end face of the cell body 11 from α to β, where β < α;

[0048] The main flattening mechanism 3 is used to perform the final flattening process on the tabs 12 after the pre-flattening process. That is, by applying pressure to the tabs 12, the tabs 12 are further bent toward the axis of the cell 1, so that the angle between the tabs 12 and the end face of the cell body 11 is reduced from β to 0°, and all the tabs 12 on each end face are stacked and pressed together to achieve a predetermined thickness and flatness.

[0049] The cell tab flattening device with the above structure first pre-flattens the tabs 12 through the pre-flattening mechanism 2, and then the main flattening mechanism 3 performs the final flattening process on the pre-flattened tabs 12. Compared with the existing technology that only sets one flattening process, this device can ensure that each layer of tabs 12 is fully flattened and compacted. This reduces the occurrence of phenomena such as the outermost tabs 12 bursting, the middle layer tabs 12 not being compacted, and gaps between tabs 12. In addition, it reduces the risk of electrolyte seeping into the gaps of the tabs 12, causing short circuits or performance degradation in the battery, and can improve battery quality and safety.

[0050] In some embodiments, the pre-flattening mechanism 2 includes a first pre-flattening component 21 and a second pre-flattening component 22, wherein:

[0051] The first pre-flattening component 21 is used to perform the initial pre-flattening process on the tab 12, that is, by applying pressure to the tab 12, the tab 12 is further bent toward the axis of the cell 1, so that the angle between the tab 12 and the end face of the cell body 11 is reduced from α to γ, where γ<α.

[0052] The second pre-flattening component 22 is used to perform a second pre-flattening process on the tab 12 after the initial pre-flattening process. That is, by applying pressure to the tab 12, the tab 12 is further bent toward the axis of the cell 1, so that the angle between the tab 12 and the end face of the cell body 11 is further reduced from γ to β, where β < γ.

[0053] The battery cell tab flattening device with the above structure performs two pre-flattening processes on the tab 12 during the pre-flattening process. The first pre-flattening component 21 and the second pre-flattening component 22 perform the pre-flattening process on the tab 12 in sequence. The angle between the tab 12 and the end face of the battery cell body 11 is gradually reduced from the initial angle α to the intermediate angle γ, and then further reduced to the final preset angle β, where α>γ>β. This multi-stage progressive flattening method can effectively alleviate the stress concentration of the tab material during the bending process, prevent the tab 12 from breaking or generating debris, and improve the bonding consistency and process stability after flattening. This significantly improves the assembly yield and subsequent welding accuracy of the battery cell 1.

[0054] In some embodiments, after the battery cell 1 is wound and before it is flattened, the initial angle α between the tab 12 and the end face of the battery cell body 11 is 70°; after the first pre-flattening component 21 performs the initial pre-flattening treatment on the tab 12, the angle γ between the tab 12 and the end face of the battery cell body 11 is 45°, that is, the initial pre-flattening treatment range is 25°; after the second pre-flattening component 22 performs the second pre-flattening treatment on the tab 12 after the initial pre-flattening treatment, the angle β between the tab 12 and the end face of the battery cell body 11 is 30°, that is, the second pre-flattening treatment range is 15°.

[0055] When the battery cell tab flattening device with the above structure is used, and the initial included angle α between the tab 12 and the end face of the battery cell body 11 is 70°, after testing, the flattening and pressing effect of the tab 12 is better when the initial pre-flattening treatment range is 25° and the secondary pre-flattening treatment range is 15° (i.e., γ = 45° after the initial pre-flattening treatment and β = 30° after the secondary pre-flattening treatment), which is beneficial to improving the production quality of the battery cell 1.

[0056] In some embodiments, the battery cell tab flattening device further includes a transmission mechanism 4, which can be used to realize the transmission of the battery cell 1, so that the battery cell 1 can move stably between different work stations. For example, in this embodiment, the transmission mechanism 4 can realize the transmission of the battery cell 1 between the first pre-flattening component 21, the second pre-flattening component 22 and the main flattening mechanism 3.

[0057] The battery cell tab flattening device with the above structure enables the battery cell 1 to move stably between different workstations through the transmission mechanism 4, which can improve the production efficiency of the battery cell 1.

[0058] In some embodiments, such as Figure 3 , Figure 4 , Figure 5 As shown, the first pre-flattening assembly 21 includes first pre-flattening units respectively disposed at both ends of the battery cell 1 (i.e., one first pre-flattening unit is disposed at each end of the battery cell 1). The first pre-flattening unit includes a first pre-flattening fixture 211 and a first pre-flattening drive component 212. The first pre-flattening fixture 211 has a first closing groove 2111 adapted to the battery cell 1 at one end near the battery cell 1. The first closing groove 2111 includes a first pre-flattening plane 21111, a first closing conical surface 21112, and a first extended conical surface 21113. The first pre-flattening plane 21111 is located at... At the bottom of the first closing groove 2111, it is opposite to the end face of the battery cell body 11; the first closing conical surface 21112 is an annular conical surface extending from the edge of the first pre-compression plane 21111, and the angle between the first closing conical surface 21112 and the first pre-compression plane 21111 is 180°-γ; the first extended conical surface 21113 is an annular conical surface in the shape of a trumpet extending from the edge of the first closing conical surface 21112; the first pre-compression flat driving component 212 can be used to drive the first pre-compression flat fixture 211 to move closer to or away from the battery cell 1 along the axial direction of the battery cell 1.

[0059] The battery cell tab flattening device with the above structure, driven by the first pre-flattening drive component 212, has the first pre-flattening fixtures 211 located at both ends of the battery cell 1 approaching the battery cell 1 along the axial direction of the battery cell 1 respectively; the first extended conical surface 21113 in the first pre-flattening fixture 211 can better guide the tab 12 into the predetermined position, realizing the positioning of the tab 12; the first tapering conical surface 21112 can tighten the tab 12 on the outer ring of the battery cell 1, and the first pre-flattening plane 21111 can apply pressure to the tab 12, flattening and tightening it, thereby causing the tab 12 to bend further toward the axis of the battery cell 1, so that the angle between the tab 12 and the end face of the battery cell body 11 is reduced from α to γ. It not only has a simple structure, but also has a good flattening effect.

[0060] In some embodiments, such as Figure 3 , Figure 6 , Figure 7 , Figure 8 As shown, the second pre-flattening assembly 22 includes a cell positioning assembly 5 and second pre-flattening units respectively disposed at both ends of the cell 1 (i.e., one second pre-flattening unit is disposed at each end of the cell 1); wherein, the second pre-flattening unit includes a second pre-flattening fixture 221 and a second pre-flattening drive component 222; the second pre-flattening fixture 221 is provided with a second closing groove 2211 adapted to the cell 1 at one end near the cell 1, the second closing groove 2211 including a second pre-flattening plane 22111 and a second closing conical surface 22112; the second pre-flattening plane 22111... 111 is located at the bottom of the second closing groove 2211 and is opposite to the end face of the cell body 11; the second closing conical surface 22112 is an annular conical surface extending from the edge of the second pre-compression plane 22111, and the angle between the second closing conical surface 22112 and the second pre-compression plane 22111 is 180°-β; the cell positioning component 5 can be used to fix the cell body 11 and realize the positioning of the cell 1; the second pre-compression flat driving component 222 can be used to drive the second pre-compression flat fixture 221 to move closer to or away from the cell 1 along the axial direction of the cell 1.

[0061] The battery cell tab flattening device with the above structure first fixes the battery cell body 11 by the battery cell positioning component 5 to achieve precise positioning of the battery cell 1; then, driven by the second pre-flattening drive component 222, the second pre-flattening fixtures 221 located at both ends of the battery cell 1 approach the battery cell 1 along the axial direction of the battery cell 1; the second concave conical surface 22112 in the second pre-flattening fixture 221 can tighten the tab 12 on the outer ring of the battery cell 1, and the second pre-flattening plane 22111 can apply pressure to the tab 12, flattening and tightening it, thereby causing the tab 12 to bend further toward the axis of the battery cell 1, so that the angle between the tab 12 and the end face of the battery cell body 11 is reduced from γ to β. It not only has a simple structure, but also has a good flattening effect.

[0062] In some embodiments, such as Figure 3 , Figure 9 , Figure 10 , Figure 11 As shown, the main flattening mechanism 3 includes a cell positioning assembly 5 and main flattening units respectively disposed at both ends of the cell 1 (i.e., one main flattening unit is disposed at each end of the cell 1); wherein, the main flattening unit includes a main flattening fixture 31 and a main flattening drive component 32; the main flattening fixture 31 is provided with a flattening groove 311 adapted to the cell 1 at one end near the cell 1, the flattening groove 311 includes a flattening end face 3111 and a closing side face 3112, the flattening end face 3111 being positioned... At the bottom of the flattening groove 311, it is opposite to the end face of the cell body 11; the constricting side 3112 is an annular surface extending from the edge of the flattening end face 3111, and the angle between the constricting side 3112 and the flattening end face 3111 is 90°; the cell positioning component 5 can be used to fix the cell body 11 to realize the positioning of the cell 1; the main flattening drive component 32 can be used to drive the main flattening fixture 31 to move closer to or away from the cell 1 along the axial direction of the cell 1.

[0063] The battery cell tab flattening device with the above structure first fixes the battery cell body 11 by the battery cell positioning component 5 to achieve precise positioning of the battery cell 1; then, driven by the main flattening drive component 32, the main flattening fixtures 31 located at both ends of the battery cell 1 approach the battery cell 1 along the axial direction of the battery cell 1; the constricting side 3112 in the main flattening fixture 31 can tighten the tabs 12 on the outer ring of the battery cell 1, and the flattening end face 3111 can apply pressure to the tabs 12 for final flattening and pressing, thereby causing the tabs 12 to bend further toward the axis of the battery cell 1, reducing the angle between the tabs 12 and the end face of the battery cell body 11 from β to 0°, and causing all the tabs 12 on each end face to be stacked and pressed together to achieve a predetermined thickness and flatness. It not only has a simple structure, but also has a good flattening effect.

[0064] In some embodiments, such as Figure 6 , Figure 7 , Figure 9 , Figure 10 As shown, the battery cell positioning assembly 5 includes a positioning gripper 51, a gripper opening and closing cylinder 52, and a gripper lifting cylinder 53. The gripper opening and closing cylinder 52 can drive the positioning gripper 51 to open or close. The gripper lifting cylinder 53 can drive the positioning gripper 51 to move up and down. The positioning gripper 51 is adapted to the side of the battery cell body 11 and can clamp the battery cell body 11 by contacting its side. Preferably, a precision pressure regulating valve can also be provided on the positioning gripper 51 to achieve more accurate and reliable clamping action.

[0065] The battery cell tab flattening device with the above structure, through the cooperation between the positioning gripper 51 and the gripper opening and closing cylinder 52, can not only stably and reliably clamp the battery cell 1 and achieve precise positioning of the battery cell 1; but also avoid interference caused by the positioning gripper 51 when it is not working, by driving the positioning gripper 51 to move up and down through the gripper lifting cylinder 53, making the battery cell tab flattening device more flexible.

[0066] In some embodiments, the main flattening drive component 32 is a servo motor, and the main flattening drive component 32 drives the main flattening fixture 31 to reach the set flattening position, stays for 1-2 seconds, and then returns to the original position.

[0067] The battery cell tab flattening device with the above structure first selects a servo motor as the main flattening drive component 32, which can accurately control the movement trajectory and termination position of the main flattening fixture 31, resulting in higher precision, faster response, and better stability. When the main flattening fixture 31 reaches the set flattening position, the servo motor controls it to hold for 1-2 seconds before resetting, which allows the tab 12 to fit more fully against the end face of the battery cell body 1 under pressure, reducing springback or warping, improving flattening consistency and process stability, and enhancing production quality.

[0068] Preferably, since the distance by which the main flattening fixture 31 moves forward and presses under the control of the servo motor is constant, 1, in order to ensure that the thickness at both ends of the battery cell 1 reaches the set value after the final flattening process, i.e. Figure 2 During the final flattening process, the process values ​​of L1 and L2 can be determined by first driving the main flattening fixtures 31 at both ends of the battery cell 1 to the desired position via a servo motor. Figure 1 The positions of both ends of H1 are pre-positioned axially, and then returned to their original positions; at this time, the battery cell 1 is clamped by the battery cell positioning component 5 for precise positioning; finally, the main flattening fixtures 31 at both ends of the battery cell 1 are driven by the servo motor to reach the position. Figure 2 The pressure is maintained at both ends of H2 for 1-2 seconds. After the flattening action is completed, the servo motor returns to its original position. This results in a better flattening and pressing effect, which can further improve the production quality of the battery cell 1.

[0069] In some embodiments, such as Figure 9 , Figure 11 As shown, an anti-blocking center pin 3113 is provided on the flattened end face 3111. The anti-blocking center pin 3113 is adapted to the liquid injection hole on the end face of the battery cell body 11 and can be inserted into the liquid injection hole to prevent the liquid injection hole from being blocked.

[0070] The battery cell tab flattening device with the above structure, by setting an anti-blocking center pin 3113 on the flattening end face 3111, can not only prevent the tab 12 from entering the injection hole and causing blockage during the flattening process, but also play a guiding and positioning role, ensuring that the material entering the flattening groove 311 each time can be accurately in the optimal flattening position, thereby improving the consistency and quality of processing.

[0071] The above embodiments are merely preferred embodiments of the present utility model and are not intended to limit the scope of implementation of the present utility model. All equivalent changes made in accordance with the shape, structure and principle of the present utility model should be covered within the protection scope of the present utility model.

Claims

1. A battery cell tab flattening device for flattening the tabs of a battery cell (1), wherein the battery cell (1) is a multi-tab cylindrical battery cell, comprising a battery cell body (11) and multiple tabs (12), wherein the tabs (12) extend from the end faces of both ends of the battery cell body (11), bend toward the axis of the battery cell (1) and are stacked, and the included angle between each tab (12) and the end face of the battery cell body (11) is α, α < 90°, characterized in that, It includes a pre-flattening mechanism (2) and a main flattening mechanism (3); The pre-flattening mechanism (2) is used to pre-flatten the tab (12). By applying pressure to the tab (12), the tab (12) is further bent toward the axis of the cell (1), so that the angle between the tab (12) and the end face of the cell body (11) is reduced from α to β, where β < α. The main flattening mechanism (3) is used to perform final flattening on the tabs (12) after pre-flattening. By applying pressure to the tabs (12), the tabs (12) are further bent toward the axis of the cell (1), so that the angle between the tabs (12) and the end face of the cell body (11) is reduced from β to 0°, and all the tabs (12) on each end face are stacked and pressed together to achieve a predetermined thickness and flatness.

2. The battery cell tab flattening device according to claim 1, characterized in that, The pre-flattening mechanism (2) includes a first pre-flattening component (21) and a second pre-flattening component (22); The first pre-flattening assembly (21) is used to perform the initial pre-flattening process on the tab (12). By applying pressure to the tab (12), the tab (12) is further bent toward the axis of the cell (1), so that the angle between the tab (12) and the end face of the cell body (11) is reduced from α to γ, where γ < α. The second pre-flattening assembly (22) is used to perform a second pre-flattening process on the tab (12) after the first pre-flattening process. By applying pressure to the tab (12), the tab (12) is further bent toward the axis of the cell (1), so that the angle between the tab (12) and the end face of the cell body (11) is further reduced from γ to β, where β < γ.

3. The battery cell tab flattening device according to claim 2, characterized in that, α=70°, γ=45°, β=30°.

4. The battery cell tab flattening device according to any one of claims 1-3, characterized in that, It also includes a transmission mechanism (4), which can be used to realize the transmission of the battery cell (1) so that the battery cell (1) can move stably between different work stations.

5. The battery cell tab flattening device according to claim 2, characterized in that, The first pre-flattening assembly (21) includes first pre-flattening units respectively disposed at both ends of the battery cell (1). The first pre-flattening unit includes a first pre-flattening fixture (211) and a first pre-flattening drive component (212). The first pre-flattening fixture (211) has a first closing groove (2111) adapted to the battery cell (1) at one end near the battery cell (1). The first closing groove (2111) includes a first pre-flattening plane (21111), a first closing conical surface (21112), and a first extended conical surface (21113). The first pre-flattening plane (21111) is located in the first closing groove (2111). The bottom of the battery cell is opposite to the end face of the battery cell body (11); the first tapered surface (21112) is an annular tapered surface extending from the edge of the first pre-pressure plane (21111), and the angle between the first tapered surface (21112) and the first pre-pressure plane (21111) is 180°-γ; the first extended tapered surface (21113) is an annular tapered surface in the shape of a trumpet extending from the edge of the first tapered surface (21112); the first pre-pressure flat driving component (212) can be used to drive the first pre-pressure flat fixture (211) to move closer to or away from the battery cell (1) along the axial direction of the battery cell (1).

6. The battery cell tab flattening device according to claim 2, characterized in that, The second pre-flattening assembly (22) includes a cell positioning assembly (5) and second pre-flattening units respectively disposed at both ends of the cell (1). The second pre-flattening unit includes a second pre-flattening fixture (221) and a second pre-flattening drive component (222). The second pre-flattening fixture (221) has a second closing groove (2211) adapted to the cell (1) at one end near the cell (1). The second closing groove (2211) includes a second pre-flattening plane (22111) and a second closing cone surface (22112). The second pre-flattening plane (22111) is located at the second The bottom of the closing groove (2211) is opposite to the end face of the cell body (11); the second closing cone surface (22112) is an annular cone surface extending from the edge of the second pre-compression plane (22111), and the angle between the second closing cone surface (22112) and the second pre-compression plane (22111) is 180°-β; the cell positioning assembly (5) can be used to fix the cell body (11); the second pre-compression flat driving component (222) can be used to drive the second pre-compression flat fixture (221) to move closer to or away from the cell (1) along the axial direction of the cell (1).

7. The battery cell tab flattening device according to claim 1, characterized in that, The main flattening mechanism (3) includes a cell positioning assembly (5) and main flattening units respectively disposed at both ends of the cell (1). The main flattening unit includes a main flattening fixture (31) and a main flattening drive component (32). The main flattening fixture (31) has a flattening groove (311) adapted to the cell (1) at one end near the cell (1). The flattening groove (311) includes a flattening end face (3111) and a closing side face (3112). The flattening end face (3111) is located in the flattening groove (3112). The bottom of 11) is opposite to the end face of the battery cell body (11); the constricted side (3112) is an annular surface extending from the edge of the flattened end face (3111), and the angle between the constricted side (3112) and the flattened end face (3111) is 90°; the battery cell positioning assembly (5) can be used to fix the battery cell body (11); the main flattening drive component (32) can be used to drive the main flattening fixture (31) to move closer to or away from the battery cell (1) along the axial direction of the battery cell (1).

8. The battery cell tab flattening device according to claim 6 or 7, characterized in that, The battery cell positioning assembly (5) includes a positioning gripper (51), a gripper opening and closing cylinder (52), and a gripper lifting cylinder (53); the gripper opening and closing cylinder (52) can drive the positioning gripper (51) to open and close; the gripper lifting cylinder (53) can drive the positioning gripper (51) to move up and down; the positioning gripper (51) is adapted to the side of the battery cell body (11) and can clamp the battery cell body (11) by contacting the side of the battery cell body (11).

9. The battery cell tab flattening device according to claim 7, characterized in that, The main flattening drive component (32) is a servo motor, and the main flattening drive component (32) drives the main flattening fixture (31) to reach the set flattening position, stay for 1-2 seconds, and then return to the original position.

10. The battery cell tab flattening device according to claim 7, characterized in that, An anti-blocking center pin (3113) is provided on the flattened end face (3111). The anti-blocking center pin (3113) is adapted to the liquid injection hole on the end face of the battery cell body (11) and can be inserted into the liquid injection hole.

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