Folding ear mechanism and pole piece structure of cylindrical battery cell

Abstract

The present invention discloses a tab folding mechanism and a pole piece structure for a cylindrical battery cell. The tab folding mechanism includes: a bracket; a feed guide unit, the feed guide unit includes a smoothing roller and a guide block, in the running direction of the pole piece structure, the guide block is located downstream of the smoothing roller, the smoothing roller is used to smooth the multiple tabs of the pole piece structure, and the guide block is used to pre-bend the multiple tabs after smoothing in a gradual bending manner; a roller mechanism is installed on the bracket, in the running direction of the pole piece structure, the roller mechanism is located downstream of the feed guide unit, and the roller mechanism is used to shape the bending angles of the multiple tabs after pre-bending. The above-mentioned tab folding mechanism first smoothes the tabs by means of the smoothing roller, and then bends the smoothed tabs by means of the guide block in a gradual bending manner, which can achieve a smooth transition of the tab bending angles and solve the tab folding problem.

Description

Technical Field

[0001] The present invention relates to the technical field of batteries, and in particular to a pole lug folding mechanism and a pole piece structure of a cylindrical battery cell. Background Art

[0002] The rapid development of the new energy vehicle industry has led to higher requirements for the energy density and rate performance of power batteries. The 46 series large cylindrical battery represents a key breakthrough. However, processing the full tabs of these large cylindrical batteries remains a technical challenge in the industry. The main processing methods include: first, flattening the entire tab using a flattening wheel; and second, beveling the tabs before folding them. However, high-speed folding of beveled tabs can lead to tab folding and insertion into the electrode sheet, posing a risk of short circuiting within the battery cell. Summary of the Invention

[0003] The present invention provides a pole lug folding mechanism and a pole piece structure of a cylindrical battery cell.

[0004] A tab folding mechanism of the present invention comprises:

[0005] Bracket;

[0006] A feed guide unit, comprising a smoothing roller and a guide block. In the running direction of the pole piece structure, the guide block is located downstream of the smoothing roller. The smoothing roller is used to smooth the multiple tabs of the pole piece structure. The guide block is used to pre-bend the multiple tabs after smoothing in a gradual bending manner.

[0007] The roller mechanism is installed on the bracket. In the walking direction of the pole piece structure, the roller mechanism is located downstream of the feed guide unit. The roller mechanism is used to shape the bending angles of the multiple pole ears after pre-bending.

[0008] The above-mentioned tab folding mechanism first smoothes the tab by means of a smoothing roller, and then bends the smoothed tab in a gradual bending manner by means of a guide block, thereby achieving a smooth transition of the tab bending angle and solving the tab folding problem.

[0009] In some embodiments, the guide block is provided with a gradual slope, and the gradual slope is used to gradually bend the tab.

[0010] In certain embodiments, a mounting groove is provided at the front end of the guide block, a bottom wall of the mounting groove is connected to the gradual slope, and the smoothing roller is partially accommodated in the mounting groove.

[0011] In certain embodiments, the circumferential side wall of the smoothing roller is provided with air blowing holes, and the air blowing holes are used to blow upward airflow toward the tab to smooth the tab or blow it to a positive angle.

[0012] In some embodiments, the pair of rollers includes a pressure roller unit and a bending roller unit, the pressure roller unit includes a rollable pressure roller, the bending roller unit includes a rollable bending roller, the pressure roller and the bending roller are used to jointly clamp the pole piece structure, and a flexible bending module is provided on one side of the bending roller, and the flexible bending module is used to shape the bending angle of the pole ear after bending.

[0013] In some embodiments, the pressing roller unit further includes an adjusting component, which is mounted on the bracket and connected to the pressing roller, and the adjusting component is used to adjust the gap between the pressing roller and the bending roller.

[0014] In some embodiments, negative pressure air holes are provided on the circumferential side walls of the bending roller, and the negative pressure air holes are used to remove dust from the pole piece structure by utilizing negative pressure.

[0015] In some embodiments, the flexible bending module includes a guide rod, a movable member and a flexible slope, wherein the movable member is movably arranged on the guide rod, one end of the flexible slope is connected to one side of the bending roller, and the other end of the flexible slope is connected to the movable member, and the movable member can move back and forth along the guide rod to adjust the inclination angle of the flexible slope.

[0016] In some embodiments, the guide rod includes a screw rod, the movable member is threadedly connected to the screw rod, and a handle is connected to the movable member. When the handle is operated, the movable member is driven to rotate so that the movable member moves back and forth on the screw rod.

[0017] In some embodiments, the pole piece structure includes a coating area and a tab area, the tab area is connected to one side of the coating area, and the head of the tab area is provided with a head cutting area, wherein the tab width of the pole piece structure is 4mm<W<8mm, the tab height is 4mm<H<8mm, the tab root height is 1mm<b<2mm, the tab inclination angle is 15°<α<30°, the inclination direction is opposite to the running direction of the pole piece structure, forming an obtuse angle, the tab gap is 2mm<δ<4mm, the tab root fillet is 1mm<R1<3mm, and 1mm<R2<3mm.

[0018] In some embodiments, the tab folding mechanism further includes a position sensor. In the walking direction of the pole piece structure, the position sensor is located upstream of the feed guide unit. The position sensor is used to detect the root position of the tab in real time.

[0019] The pole piece structure of a cylindrical battery cell of the present invention comprises:

[0020] coating area, and

[0021] The tab area is connected to one side of the coating area, the tab area is provided with a head cutting area at the head of the tab area, the tab area is provided with multiple tabs, the tab width is 4mm<W<8mm, the tab height is 4mm<H<8mm, the tab root height is 1mm<b<2mm, the tab inclination angle is 15°<α<30°, the inclination direction is opposite to the running direction of the pole piece structure, forming an obtuse angle, the tab gap is 2mm<δ<4mm, the tab root fillet is 1mm<R1<3mm, and 1mm<R2<3mm.

[0022] The pole piece structure of the above cylindrical battery cell avoids stress concentration and damage to the pole ear through the rounded corner design and tilt angle design at the base of the pole ear.

[0023] Additional aspects and advantages of the present invention will be set forth in part in the description which follows and, in part, will be obvious from the description which follows, or may be learned by practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying any creative work.

[0025] Figure 1 It is a three-dimensional schematic diagram of the tab folding mechanism of the present invention;

[0026] Figure 2 is another three-dimensional schematic diagram of the tab folding mechanism of the present invention;

[0027] Figure 3 Schematic diagram of the structure of the pole piece structure of the present invention;

[0028] Figure 4 yes Figure 3 Enlarged view of part A;

[0029] Figure 5 is another three-dimensional schematic diagram of the pole piece structure of the present invention;

[0030] Figure 6 yes Figure 5 Enlarged view of part B;

[0031] Figure 7 This is a schematic diagram of the connection between the smoothing roller and the guide block of the present invention;

[0032] Figure 8 1 is a schematic diagram of the smoothing roller and the guide block of the present invention;

[0033] Figure 9 It is a structural schematic diagram of the roller mechanism of the present invention;

[0034] Figure 10 It is a three-dimensional schematic diagram of the roller mechanism of the present invention;

[0035] Figure 11 is a schematic structural diagram of the stent of the present invention;

[0036] Figure 12 is a three-dimensional schematic diagram of a pressure roller unit of the present invention;

[0037] Figure 13 is a schematic cross-sectional view of a pressure roller unit of the present invention;

[0038] Figure 14 is a three-dimensional schematic diagram of a bending roller unit of the present invention;

[0039] Figure 15 is a schematic cross-sectional view of a bending roller unit of the present invention;

[0040] Figure 16 yes Figure 15 Enlarged view of part C;

[0041] Figure 17 It is a cross-sectional view of the flexible bending module of the present invention. DETAILED DESCRIPTION

[0042] The embodiments of the present invention are described in detail below. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention and are not to be construed as limiting the present invention.

[0043] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more features. In the description of the present invention, the meaning of "multiple" is two or more, unless otherwise clearly and specifically defined.

[0044] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood broadly. For example, they may refer to fixed connections, removable connections, or integral connections. They may refer to mechanical connections or electrical connections. They may refer to direct connections or indirect connections through an intermediary, and they may refer to internal communication between two components or interactions between two components. Those skilled in the art will understand the specific meanings of these terms in the present invention based on the specific circumstances.

[0045] In the present invention, unless otherwise expressly specified or limited, a first feature being "above" or "below" a second feature may include the first and second features being in direct contact, or may include the first and second features being in contact not directly but through another feature between them. Furthermore, a first feature being "above," "above," and "above" a second feature may include the first feature being directly above or obliquely above the second feature, or may simply mean that the first feature is higher in level than the second feature. A first feature being "below," "below," and "below" a second feature may include the first feature being directly below or obliquely below the second feature, or may simply mean that the first feature is lower in level than the second feature.

[0046] The disclosure below provides many different embodiments or examples for realizing different structures of the present invention. In order to simplify the disclosure of the present invention, the components and settings of specific examples are described below. Of course, they are merely examples and are not intended to limit the present invention. In addition, the present invention may repeat reference numbers and / or reference letters in different examples. Such repetition is for the purpose of simplicity and clarity and does not in itself indicate the relationship between the various embodiments and / or settings discussed. In addition, the present invention provides examples of various specific processes and materials, but those skilled in the art will recognize the application of other processes and / or the use of other materials.

[0047] Please refer to Figures 1 to 8 The present invention proposes a tab folding mechanism 100 including a bracket 12 , a feed guide unit 14 and a roller mechanism 16 .

[0048] The feeding guide unit 14 includes a smoothing roller 18 and a guide block 20, which is arranged in the direction of the pole piece structure 22 (eg Figure 1 and Figure 2 The guide block 20 is located downstream of the smoothing roller 18, and the smoothing roller 18 is used to smooth the multiple pole ears 24 of the pole piece structure 22. The guide block 20 is used to pre-bend the smoothed multiple pole ears 24 in a gradual bending manner.

[0049] The roller mechanism 16 is installed on the bracket 12 and is located downstream of the feed guide unit 14 in the running direction of the pole piece structure 22 . The roller mechanism 16 is used to shape the bending angles of the multiple pole tabs 24 after bending.

[0050] The tab folding mechanism 100 first smoothes the tab 24 through the smoothing roller 18 and then bends the smoothed tab 24 in a gradual bending manner through the guide block 20, thereby achieving a smooth transition of the bending angle of the tab 24 and solving the problem of the tab 24 folding.

[0051] Specifically, in the present invention, the pole piece structure 22 can be applied to cylindrical cells, and the pole piece structure 22 can be a multi-pole ear pole piece structure. Figures 3 to 6 The pole piece structure 22 includes a coating area 26 and a tab area 28. A head cutting area 30 is designed at the head of the tab area 28. The width of the tab 24 is 4mm<W<8mm, the height of the tab 24 is 4mm<H<8mm, the height of the base of the tab 24 is 1mm<b<2mm, the inclination angle of the tab 24 is 15°<α<30°, and the inclination direction is opposite to the running direction of the pole piece structure 22, forming an obtuse angle. The gap between the tabs 24 is 2mm<δ<4mm, the fillet of the base of the tab 24 is 1mm<R1<3mm, and 1mm<R2<3mm. After passing through the tab folding mechanism 100, the tab 24 is bent at an angle of 45°-75°, with a typical value of 60°±5°.

[0052] The head cutting area 30 is an area without a pole ear 24 at one end of the pole piece structure 22. The length of the head cutting area 30 can be pre-set. The setting of the head cutting area 30 can ensure that when the pole piece structure 22 is rolled up, the pole piece structure 22 will not block the center hole of the winding core.

[0053] The bracket 12 may be a frame-shaped bracket, and the rollers of the roller mechanism 16 may be partially located in the space of the frame-shaped bracket 12 to support and install the roller mechanism 16 .

[0054] In the running direction of the pole piece structure 22, the guide block 20 is located downstream of the smoothing roller 18, so that the smoothing roller 18 can first smooth the pole tab 24, and then use the guide block 20 to gradually bend the pole tab 24 to pre-bend the pole tab 24. The so-called gradual bending is a method of smoothly increasing or steplessly increasing the bending angle of the pole tab 24 to avoid sudden bending of the pole tab 24 and breaking the pole tab 24.

[0055] In the direction of travel of the pole piece structure 22, the roller mechanism 16 is located downstream of the feed guide unit 14, so that the roller mechanism 16 can shape the bending angle of the pre-bent tab 24. For example, the bending angle of the tab 24 can be increased or decreased as needed, or remain unchanged. The bending angle of the tab 24 can be the angle between the plane where the tab 24 is located and a reference plane. The reference plane can be the plane where the coating area 26 is located, or other reference plane.

[0056] In the present invention, please refer to Figure 7 and Figure 8 The guide block 20 is provided with a gradual slope 32, which is used to gradually bend the tab 24. In this way, a gradual change in the bending angle of the tab 24 can be achieved.

[0057] Specifically, the gradual ramp 32 can achieve a gradual change in the angle of the slope from the entry ramp end to the exit ramp end. For example, the angle at the entry ramp end is 0 degrees or 10 degrees, and the angle at the exit ramp end is 70 degrees or 75 degrees. That is, when entering the gradual ramp 32, the tab 24 can have a bending angle of 0 degrees or 10 degrees, or between 0 degrees and 10 degrees. When the tab 24 exits the gradual ramp 32, the tab 24 can have a bending angle of 70 degrees or 75 degrees, or between 70 degrees and 75 degrees. After the tab 24 exits the gradual ramp 32, the tab 24 will rebound by a certain angle, for example, 10 degrees to 15 degrees. That is, before entering the roller mechanism 16, the bending angle of the tab 24 will be 10-15 degrees smaller than the bending angle of the tab 24 when it exits the guide block 20.

[0058] In the present invention, the front end of the guide block 20 is provided with a mounting groove 34, the bottom wall of the mounting groove 34 is connected to the gradual slope 32, and the smoothing roller 18 is partially accommodated in the mounting groove 34. In this way, the smoothing roller 18 and the guide block 20 can be seamlessly connected.

[0059] Specifically, the smoothing roller 18 can be cylindrical, and the mounting groove 34 can be arc-shaped to accommodate the shape of the smoothing roller 18. When the smoothing roller 18 is placed in the mounting groove 34, a seamless connection between the smoothing roller 18 and the guide block 20 can be achieved. Furthermore, the tangent direction of the top of the smoothing roller 18 falls on the gradually changing slope 32, so that the tab 24 can directly rest on the gradually changing slope 32 after passing through the smoothing roller 18, achieving continuous smoothing and bending of the tab 24.

[0060] In the present invention, the circumferential sidewall of the smoothing roller 18 is provided with air holes 36, which are used to blow upward airflow to the tab 24 to smooth the tab 24. In this way, the tab 24 can be smoothed while avoiding scratching the tab 24.

[0061] Specifically, by using an upward airflow to blow toward the tab 24 to smooth the tab 24 , it is possible to avoid scratching the tab 24 by smoothing the tab 24 with an object in contact with the tab 24 .

[0062] The smoothing roller 18 may include a sleeve 38 and a smoothing roller shaft 40. The sleeve 38 defines a roller mounting hole 42, into which the smoothing roller shaft 40 is mounted. The smoothing roller shaft 40 defines an air passage 44. The air hole 36 extends through the sleeve 38 and the smoothing roller shaft 40. The air passage 44 communicates with the air hole 36. The air passage 44 may be connected to an external compressed air source, and the air hole 36 may flatten the folded tab 24. Flattening may refer to a bending angle of 0 degrees, or a difference between the bending angle and 0 degrees within a set range.

[0063] In the present invention, the air holes 36 are used to blow upward airflow to the tabs 24 to blow the tabs 24 to a positive angle. In this way, the tabs 24 can have a certain bending angle when entering the guide block 20.

[0064] Specifically, a positive angle may refer to an upward inclination of the tab 24 relative to a reference plane. In the present invention, the upward inclination angle may be between 0 and 10 degrees. In one example, the upward inclination angle is 10 degrees, and the gradual slope 32 provided on the guide block 20 can achieve a gradual bend of the tab 24 from 10 degrees to 60 degrees.

[0065] In the present invention, please refer to Figure 9 、 Figure 10 、 Figure 12 and Figure 14 The roller mechanism 16 includes a pressing roller unit 46 and a bending roller unit 48. The pressing roller unit 46 includes a rollable pressing roller 50, and the bending roller unit 48 includes a rollable bending roller 52. The pressing roller 50 and the bending roller 52 are used to clamp the electrode structure 22. A flexible bending module 54 is provided on one side of the bending roller 52. The flexible bending module 54 is used to adjust the bending angle of the bent tab 24. In this way, the bending angle of the tab 24 can be formed.

[0066] For details, please refer to Figures 11 to 15 The bracket 12 is provided with a pressure roller center axis hole 56 and a bending roller center axis hole 58. The pressure roller 50 can be installed on the bracket 12 through the pressure roller center axis hole 56, and the bending roller 52 is installed on the bracket 12 through the bending roller center axis hole 58, and is located below the pressure roller 50. The two ends of the pressure roller 50 are connected to the pressure roller center axis 64 through the pressure roller bearings 62, and the two ends of the pressure roller center axis 64 are installed in the pressure roller center axis hole 56.

[0067] The pressure roller 50 can rotate around the pressure roller bearing 62. When the pole piece structure 22 passes over the roller, the pressure roller 50 is in a follow-up state. The two ends of the bending roller 52 are connected to the bending roller center shaft 68 through the bending roller bearing 66.

[0068] The flexible bending module 54 is arranged on the right side of the bending roller 52. The diameter of the bending roller center hole 69 is larger than the diameter of the bending roller center axis 68. The bending roller 52 can rotate around the bending roller bearing 66 with clearance fit. When the pole piece structure 22 passes the roller, the bending roller 52 is in a follow-up state.

[0069] In the present invention, the pressure roller unit 46 further includes an adjustment assembly 70, which is mounted on the bracket 12 and connected to the pressure roller 50. The adjustment assembly 70 is used to adjust the gap between the pressure roller 50 and the bending roller 52. In this way, the gap between the pressure roller 50 and the bending roller 52 can be adjusted.

[0070] Specifically, the pressure roller unit 46 further includes a movable frame 72, both ends of which are connected to the pressure roller central axis 64. The adjustment assembly 70 can be connected to the movable frame 72, and the gap between the pressure roller 50 and the bending roller 52 can be adjusted by moving the movable frame 72 to accommodate electrode sheet structures 22 of different thicknesses. For example, the thickness of the positive electrode sheet structure and the negative electrode sheet structure are different. By adjusting the adjustment assembly 70, the gap between the pressure roller 50 and the bending roller 52 can be adjusted to accommodate the positive electrode sheet structure or the negative electrode sheet structure.

[0071] In the present invention, the adjustment assembly 70 includes a plurality of (two or more than two) adjustment members 74, which may be micrometers. The plurality of micrometers are arranged along the axial direction of the pressure roller 50. The bracket 12 is provided with a micrometer mounting hole 76, in which the micrometer is mounted, and the shaft end is connected to the movable bracket 72. Figure 12 In the embodiment, three micrometers are evenly distributed on the top of the movable frame 72, which can accurately control the up and down movement of the movable frame 72, thereby controlling the up and down movement of the pressure roller center shaft 64 in the pressure roller center shaft hole 56, and accurately adjusting the gap between the pressure roller 50 and the bending roller 52. It is understood that the adjustment assembly 70 can also include a single adjustment member 74, or other types of adjustment members 74, such as a cylinder.

[0072] In the present invention, negative pressure pores 78 are provided on the circumferential sidewalls of the bending roller 52. The negative pressure pores 78 are used to remove dust from the electrode structure 22 by using negative pressure. This can prevent dust from entering the battery cell and causing the risk of short circuit within the battery cell.

[0073] Specifically, the two ends of the bending roller 52 are connected to the bending roller central shaft 68 via the bending roller bearings 66. A negative pressure air pipe channel 80 is provided at the center of the bending roller central shaft 68. Negative pressure air holes 78 are provided on the circumferential sidewalls of the bending roller 52, and the negative pressure air holes 78 are connected to the negative pressure air pipe channel 80. The negative pressure air pipe channel 80 can be connected to an external negative pressure air source to provide negative pressure. The provision of the negative pressure air holes 78 can eliminate dust generated by friction when the pole piece structure 22 passes over the roller, reducing the risk of short circuits within the battery cell.

[0074] In the present invention, the flexible bending module 54 includes a guide rod 82, a movable member 84, and a flexible slope 86. The movable member 84 is movably disposed on the guide rod 82. One end of the flexible slope 86 is connected to one side of the bending roller 52, and the other end of the flexible slope 86 is connected to the movable member 84. The movable member 84 can move back and forth along the guide rod 82 to adjust the inclination angle of the flexible slope 86. In this way, the inclination angle of the flexible slope 86 can be adjusted, thereby achieving an adjustable bending angle of the tab 24, thereby solving the problem of tearing at the root of the tab 24.

[0075] Specifically, please combine Figure 16 and Figure 17 When the moving member 84 moves to the left, the other end of the flexible slope 86 moves to the left, causing the inclination angle of the flexible slope 86 to increase. When the moving member 84 moves to the right, the other end of the flexible slope 86 moves to the right, causing the inclination angle of the flexible slope 86 to decrease. The inclination angle of the flexible slope 86 is 45°<β<75°.

[0076] After the tab 24 is bent by the flexible slope 86 , the bending angle of the tab 24 is the same as the inclination angle of the flexible slope 86 . The so-called same can be exactly the same, or the difference between the two can be within a set range, or within an error range, thereby achieving the shaping of the bending angle of the tab 24 .

[0077] In the present invention, the guide rod 82 includes a screw rod, and the moving member 84 is threadedly connected to the screw rod. The moving member 84 is connected to a handle 88. The handle 88 is used to drive the moving member 84 to rotate when operated so that the moving member 84 moves back and forth on the screw rod. In this way, the position of the moving member 84 can be easily adjusted.

[0078] Specifically, the moving member 84 may include a moving ring 90, a ramp bearing 92 and a nut slider 94. The moving ring 90 and the nut slider 94 are respectively connected to the outer ring and the inner part of the ramp bearing 92. The handle 88 may be set on the nut slider 94, and the nut slider 94 is connected to the screw by a thread. A fixed ring 96 is provided on the right side of the bending roller 52. One end of the flexible ramp 86 is fixed to the fixed ring 96, and the other end of the flexible ramp 86 is fixed to the moving ring 90. When the operator operates the handle 88 to rotate around the screw, the handle 88 drives the nut slider 94 to rotate on the screw, and then the nut slider 94 can move left and right along the axial direction of the screw to adjust the inclination angle of the flexible ramp 86.

[0079] In the present invention, the pole piece structure 22 includes a coating area 26 and a tab area 28. The tab area 28 is connected to one side of the coating area 26. A head cutting area 30 is provided at the head of the tab area 28. The width of the tab 24 is 4mm < W < 8mm, the height of the tab 24 is 4mm < H < 8mm, the height of the base of the tab 24 is 1mm < b < 2mm, and the inclination angle of the tab 24 is 15° < α < 30°. The inclination direction is opposite to the running direction of the pole piece structure 22, forming an obtuse angle. The tab 24 gap is 2mm < δ < 4mm, and the base fillet of the tab 24 is 1mm < R1 < 3mm and 1mm < R2 < 3mm. In this way, the design of the base fillet of the tab 24 and the inclination angle can avoid stress concentration and damage to the tab 24.

[0080] Specifically, in the present invention, the width of the tab 24 is 4 mm < W < 8 mm, and the width W of the tab 24 can be 4.1 mm, 5 mm, 6 mm, 7.9 mm, or other values ​​between 4 mm and 8 mm.

[0081] In the present invention, the height of the tab 24 is 4 mm < H < 8 mm, and the height H of the tab 24 can be 4.1 mm, 5 mm, 6 mm, 7.9 mm, or other values ​​between 4 mm and 8 mm.

[0082] In the present invention, the height b of the base of the tab 24 is 1 mm < b < 2 mm, and the height b of the base of the tab 24 can be 1.1 mm, 1.3 mm, 1.5 mm, 1.9 mm, or other values ​​between 1 mm and 2 mm.

[0083] In the present invention, the inclination angle of the tab 24 is 15°<α<30°, and the inclination angle α of the tab 24 can be 15.5°, 16°, 17°, 19°, 20°, 23°, 25°, 27°, 29°, 29.5° or other values ​​between 15° and 30°.

[0084] The tilt direction of the pole ear 24 is opposite to the running direction of the pole piece structure 22, forming an obtuse angle. For example, please combine Figure 3 and Figure 4 The pole piece structure 22 runs forward, and the tab 24 tilts backward, forming an obtuse angle between the pole piece structure 22 running direction and the tab 24 tilt. The tab 24 tilts in the opposite direction to the running direction of the pole piece structure 22, allowing the middle of the tab 24 to pass the roller first, preventing the tail of the tab 24 from passing the roller first and causing damage.

[0085] In the present invention, the tab 24 gap 2mm<δ<4mm, and the tab 24 gap δ can be 2.1mm, 3mm, 3.5mm, 3.9mm or other values ​​between 2mm and 4mm.

[0086] In the present invention, the base fillet of the tab 24 is 1 mm < R1 < 3 mm. The base fillet R1 of the tab 24 can be 1.1 mm, 1.5 mm, 2 mm, 2.5 mm, 2.9 mm, or other values ​​between 1 mm and 3 mm. The base fillet R1 of the tab 24 can refer to the fillet at the front edge of the base of the tab 24.

[0087] In the present invention, the base radius of the tab 24 is 1mm < R2 < 3mm. The base radius R2 of the tab 24 can be 1.1mm, 1.5mm, 2mm, 2.5mm, 2.9mm, or other values ​​between 1mm and 3mm. The base radius R2 of the tab 24 refers to the radius behind the base of the tab 24. R1 and R2 can be equal or unequal, and are not specifically limited here. The base radius of the tab 24 is designed to avoid stress concentration.

[0088] In the present invention, the tab 24 is bent at an angle of 45° to 75° after passing through the tab folding mechanism 100. Thus, the tab 24 has an appropriate bending angle.

[0089] Specifically, the bending angle of the tab 24 after passing through the tab folding mechanism 100 can be 45°, 46°, 50°, 55°, 60°, 65°, 70°, 74°, 75° or other values ​​between 45° and 75°.

[0090] The bending angle of the tab 24 after passing through the tab folding mechanism 100 can be adjusted by the guide block 20 and the flexible slope 86. Specifically, the bending angle of the tab 24 when it comes out of the guide block 20 is 10-15 degrees greater than that of the flexible slope 86. After the tab 24 comes out of the guide block 20, there will be a rebound in the bending angle, and the bending angle of the tab 24 will be reduced by 10-15 degrees after the tab 24 comes out of the guide block 20. By setting the angle of the slope end of the guide block 20 to be 10-15 degrees greater than the flexible slope 86, the tab 24 can transition more smoothly from the guide block 20 to the flexible slope 86. The angle of the flexible slope 86 can be automatically adjusted, and the bending angle of the tab 24 can be adjusted in real time.

[0091] In the present invention, the smoothing roller 18 can be a rubber roller, which can be coated with Teflon. The surface roughness of the smoothing roller 18 where it contacts the tab 24 is Ra = 0.8. The guide block 20 can be made of polyetheretherketone (PEEK) and can be coated with Teflon. The surface roughness of the guide block 20 where it contacts the tab 24 is Ra = 0.8. The pressure roller 50 can be a rubber roller. The bending roller 52 can be an aluminum roller. The flexible ramp 86 can be made of elastic rubber and have a certain degree of elasticity. The surface roughness of the flexible ramp 86 where it contacts the tab 24 is Ra = 0.8.

[0092] In the present invention, the bending point of the tab 24 is 0.5 mm to 1.2 mm higher than the base of the tab 24 , so as to ensure that the tab 24 is not easily broken.

[0093] Specifically, in order to ensure a good bending effect and not to break the tab 24, the bending point of the tab 24 is 0.5mm-1.2mm higher than the root of the tab 24, that is, the bending point of the tab 24 is 0.5mm-1.2mm higher than the root of the tab 24. Figure 4 As shown, the bending point is on the dot-dashed line. The dot-dashed line represents the edge of the pressure roller 50. The pressure roller 50 can be aligned with the bending roller 52.

[0094] The bending point of the tab 24 is 0.5mm-1.2mm higher than the root of the tab 24 , and may be 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1mm, 1.2mm or other values ​​between 0.5mm-1.2mm.

[0095] In the present invention, the tab folding mechanism 100 further includes a position sensor 98. The position sensor 98 is located upstream of the feed guide unit 14 in the direction of travel of the pole piece structure 22. The position sensor 98 is used to detect the root position of the tab 24 in real time. This allows the root position of the tab 24 to be detected, facilitating real-time correction of the position of the pole piece structure 22.

[0096] Specifically, in order to ensure a good bending effect, the bending point height of the tab 24 is 0.5-1.2 mm higher than the base of the tab 24. Figure 4 As shown, the bending point is on the dotted line. The dotted line represents the edge of the pressure roller 50. The pressure roller 50 can be aligned with the bending roller 52. By adjusting the edge position of the pressure roller 50, the bending point of the tab 24 can be adjusted in real time.

[0097] During the bending process, the position of the pole piece may deviate from the originally set position. By providing a position sensor 98, the base position of the pole tab 24 can be detected in real time. If the base 7 of the pole tab 24 deviates from the set position, the position of the pole piece structure 22 can be adjusted using a movable mechanism to correct the left and right position of the pole piece structure 22, thereby avoiding stress concentration that could cause tearing at the base of the pole tab 24.

[0098] In the present invention, the pole piece is set at a position where the base of the tab 24 is 0.5 mm to 1.2 mm lower than the bending point of the tab 24. When the position sensor 98 detects that the base of the tab 24 deviates from the above distance range, it can be considered that the pole piece has deviated from the set position.

[0099] In the present invention, position sensor 98 comprises a fiber optic sensor, which includes a light emitter 97 and a light receiver 95. The light emitter 97 and the light receiver 95 are respectively arranged on the upper and lower sides of the pole piece structure 22. By calibrating the position of the fiber optic sensor, when the pole piece structure 22 is in the set position, the light receiver 95 can receive the light emitted by the light emitter 97 and passing through the gap between the two pole lugs 24. At this time, when the pole piece structure 22 is transported, the light receiver 95 can output a pulse signal of a certain period. When the pole piece structure 22 deviates from the set position, the light receiver 95 does not output a pulse signal, or the output pulse signal period becomes longer or shorter.

[0100] It is understood that the position sensor 98 may also include a camera, and the image of the pole piece structure 22 and the reference object captured by the camera are analyzed to obtain the position of the pole piece root, thereby determining whether the pole piece has deviated from the set position. The reference object may be a component of the tab folding mechanism 100 or other reference object, and is not specifically limited here.

[0101] The present invention provides a cylindrical battery cell electrode structure 22 comprising:

[0102] coating zone 26, and

[0103] The tab area 28 is connected to one side of the coating area 26. A head cutting area 30 is provided at the head of the tab area 28. The width of the tab 24 is 4mm<W<8mm, the height of the tab 24 is 4mm<H<8mm, the height of the root of the tab 24 is 1mm<b<2mm, the inclination angle of the tab 24 is 15°<α<30°, and the inclination direction is opposite to the running direction of the pole piece structure 22, forming an obtuse angle. The gap of the tab 24 is 2mm<δ<4mm, and the fillet of the root of the tab 24 is 1mm<R1<3mm, and 1mm<R2<3mm.

[0104] The pole piece structure 22 of the cylindrical battery cell avoids stress concentration and damage to the pole tab 24 by designing the rounded corners and tilt angles at the base of the pole tab 24 .

[0105] In the present invention, the bending angle of the tab 24 is 45°-75°. Thus, the bending angle of the tab 24 is appropriate.

[0106] In the present invention, the bending angle of the tab 24 is 60°±5°, which is more appropriate.

[0107] Specifically, the bending angle of the tab 24 after passing through the tab folding mechanism 100 can be 55°, 56°, 57°, 58°, 59°, 60°, 61°, 62°, 63°, 64°, 65° or other values ​​between 55° and 65°.

[0108] In summary, the electrode tab folding mechanism 100 and the electrode piece structure 22 of the present invention can achieve at least the following effects:

[0109] 1. The smoothing roller 18 is provided with circumferential blowing holes 36 to blow air toward the tab 24 from below, ensuring that the tab 24 angle is greater than 0°. The smoothing roller 18 and the guide block 20 are seamlessly connected to avoid collision and folding of the tail of the tab 24. The gradual slope 32 of the guide block 20 is used to achieve a smooth transition. The tab 24 angle can be gradually changed from 10° to 60°, for example, to solve the tab 24 folding problem.

[0110] 2. The root of the tab 24 of the present invention adopts a rounded corner design, and the bending point is 0.5mm-1.2mm away from the root of the tab 24 to avoid stress concentration. The inclination direction of the tab 24 is opposite to the running direction of the pole piece structure 22, so that the middle part of the tab 24 passes the roller first, avoiding the tail of the tab 24 from being damaged by collision when passing the roller first. The bending angle can be adjusted by the flexible slope 86 to solve the problem of tearing at the root of the tab 24.

[0111] 3. The present invention can use a micrometer to accurately adjust the gap between the rollers (the pressing roller 50 and the bending roller 52). The bending roller 52 is designed with negative pressure air holes 78 around its circumference to remove dust. This solves the problem of dust generated by friction when the pole piece structure 22 passes through the rollers, thereby reducing the risk of short circuits in the battery cell.

[0112] Although the technical solutions of the present invention have been shown and described, those skilled in the art will appreciate that various changes, modifications, substitutions and variations may be made to the technical solutions without departing from the principles and purpose of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims

1. A folding lug mechanism, characterized in that: include: Bracket (12); A feeding guide unit (14), the feeding guide unit (14) comprising a smoothing roller (18) and a guide block (20), wherein in the running direction of the pole piece structure (22), the guide block (20) is located downstream of the smoothing roller (18), the smoothing roller (18) is used to smooth the plurality of pole tabs (24) of the pole piece structure (22), and the guide block (20) is used to pre-bend the smoothed plurality of pole tabs (24) in a gradual bending manner; A roller mechanism (16) is mounted on the bracket (12). In the running direction of the pole piece structure (22), the roller mechanism (16) is located downstream of the feed guide unit (14). The roller mechanism (16) is used to shape the bending angles of the plurality of pole tabs (24) after pre-bending.

2. The electrode ear folding mechanism according to claim 1, characterized in that: The guide block (20) is provided with a gradual slope (32), and the gradual slope (32) is used to gradually bend the tab (24).

3. The electrode ear folding mechanism according to claim 2, characterized in that: A mounting groove (34) is provided at the front end of the guide block (20), the bottom wall of the mounting groove (34) is connected to the gradual slope (32), and the smoothing roller (18) is partially accommodated in the mounting groove (34).

4. The electrode ear folding mechanism according to claim 1, characterized in that: The circumferential side wall of the smoothing roller (18) is provided with a blowing hole (36), and the blowing hole (36) is used to blow an upward airflow to the pole tab (24) to smooth the pole tab (24) or blow it to a positive angle.

5. The electrode ear folding mechanism according to claim 1, characterized in that: The roller mechanism (16) includes a pressing roller unit (46) and a bending roller unit (48), wherein the pressing roller unit (46) includes a rollable pressing roller (50), and the bending roller unit (48) includes a rollable bending roller (52), wherein the pressing roller (50) and the bending roller (52) are used to jointly clamp the pole piece structure (22), and a flexible bending module (54) is provided on one side of the bending roller (52), and the flexible bending module (54) is used to adjust the bending angle of the pole tab (24) after bending.

6. The electrode ear folding mechanism according to claim 5, characterized in that: The pressing roller unit (46) further comprises an adjusting assembly (70), wherein the adjusting assembly (70) is mounted on the bracket (12) and connected to the pressing roller (50), and the adjusting assembly (70) is used to adjust the gap between the pressing roller (50) and the bending roller (52).

7. The electrode ear folding mechanism according to claim 5, characterized in that: Negative pressure air holes (78) are provided on the circumferential side wall of the bending roller (52), and the negative pressure air holes (78) are used to remove dust from the pole piece structure (22) by using negative pressure.

8. The electrode ear folding mechanism according to claim 5, characterized in that: The flexible bending module (54) includes a guide rod (82), a moving member (84) and a flexible slope (86), wherein the moving member (84) is movably arranged on the guide rod (82), one end of the flexible slope (86) is connected to one side of the bending roller (52), and the other end of the flexible slope (86) is connected to the moving member (84), and the moving member (84) can move back and forth along the guide rod (82) to adjust the inclination angle of the flexible slope (86).

9. The electrode ear folding mechanism according to claim 8, characterized in that: The guide rod (82) includes a screw rod, the moving member (84) is threadedly connected to the screw rod, and the moving member (84) is connected to a handle (88). When the handle (88) is operated, it drives the moving member (84) to rotate so that the moving member (84) moves back and forth on the screw rod.

10. The electrode ear folding mechanism according to claim 1, characterized in that: The pole piece structure (22) includes a coating area (26) and a tab area (28), wherein the tab area (28) is connected to one side of the coating area (26), and a head cutting area (30) is provided at the head of the tab area (28), wherein the tab (24) of the pole piece structure (22) has a width of 4mm<W<8mm, a height of 4mm<H<8mm, a height of the base of the tab (24) of 1mm<b<2mm, an inclination angle of the tab (24) of 15°<α<30°, and the inclination direction is opposite to the running direction of the pole piece structure (22), forming an obtuse angle, a gap of the tab (24) of 2mm<δ<4mm, and a fillet of the base of the tab (24) of 1mm<R1<3mm, and 1mm<R2<3mm.

11. The electrode ear folding mechanism according to claim 1, characterized in that: The tab folding mechanism (100) further includes a position sensor (98). In the running direction of the pole piece structure (22), the position sensor (98) is located upstream of the feed guide unit (14). The position sensor (98) is used to detect the root position of the tab (24) in real time.

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