Pole piece and indentation device

Abstract

The utility model relates to the technical field of battery manufacturing, and provides a pole piece and an indentation device. Wherein the pole piece comprises a current collector and a tab, at least one tab is arranged on one side of the current collector in a first direction, at least part of the tab is sunken to form a first groove, and the first groove extends along the first direction. The first grooves are formed in the tabs, so that the tabs are provided with uneven surfaces, the risk that the tabs are turned over and cracked when the pole pieces are conveyed is reduced, and the safety performance of the battery is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of battery manufacturing, in particular to a pole piece and an indentation device. Background Art

[0002] In lithium batteries, the tabs on the pole pieces are the bridges connecting the inside and outside of the battery. The tabs on the pole pieces are made by die-cutting foil. After the tabs are laser die-cut, when passing through rollers, pressure rollers, and conveying stations, the tabs are prone to wrinkles, folds, cracks, and other undesirable phenomena, which can lead to short circuits at the tab positions, poor welding, etc., and thus affect the performance of the battery cells. Utility Model Content

[0003] The utility model aims to provide a pole piece and an indentation device, aiming to solve the technical problem that the existing pole ear is prone to wrinkles, folds, cracks and other undesirable phenomena during the pole piece conveying process.

[0004] In a first aspect, the present application provides a pole piece, including a current collector and a pole ear, wherein at least one pole ear is provided on one side of the current collector in a first direction, and at least a portion of the pole ear is recessed to form a first groove, and the first groove extends along the first direction.

[0005] Optionally, the first direction is a width direction of the current collector.

[0006] Optionally, one end of the first groove extends to the edge of the electrode lug, and the other end of the first groove extends to the junction between the electrode lug and the current collector.

[0007] Optionally, the number of the first grooves is 1 to 3.

[0008] Optionally, the number of the first grooves is at least two, all the first grooves are arranged at intervals along the second direction, the center distance L between two adjacent first grooves is 1 to 5 mm, and the second direction is perpendicular to the first direction.

[0009] Optionally, at least a portion of the tab protrudes to form a first protrusion, and the first groove is provided corresponding to the first protrusion and is respectively located on two opposite sides of the tab to form an arch structure.

[0010] Optionally, the cross section of the first groove is trapezoidal.

[0011] In the second aspect, the present application provides an indentation device, including a pressing piece, a mating piece and a driving mechanism, the pressing piece includes a main body and a plurality of bosses, all of the bosses are arranged at intervals on the main body, the bosses extend along a third direction, the third direction is perpendicular to the running direction of the pole piece material strip, the mating piece is arranged opposite to the mating piece, and the driving mechanism is used to drive the pressing piece and / or the mating piece so that the pressing piece and the mating piece jointly extrude the pole ear.

[0012] Optionally, the main body is cylindrical, all bosses are arranged at intervals along the circumference of the main body, the third direction is the axial direction of the main body, and the driving mechanism is used to drive at least one of the pressure piece and the mating piece to rotate, wherein the mating piece is engaged with the pressure piece, or the mating piece is cylindrical, and a rubber layer is provided on the surface of the mating piece.

[0013] Optionally, the main body has a first plane, all the bosses are spaced apart on the first plane, the mating piece has a second plane opposite to the first plane, the second plane is provided with a second groove for accommodating the bosses, and the driving mechanism is used to drive at least one of the pressing piece and the mating piece so that the pressing piece and the mating piece move closer to or away from each other.

[0014] Optionally, the height of the boss is 0.5-4 mm.

[0015] Optionally, the boss has two wall surfaces that are arranged opposite to each other, and an angle α is formed between the two wall surfaces. The angle α ranges from 10° to 135°.

[0016] The pole piece provided by the utility model has the beneficial effect that the pole piece is provided with a first groove so that the pole piece is formed with an uneven surface, which is beneficial to reduce the risk of the pole piece folding or cracking when the pole piece is conveyed, thereby improving the safety performance of the battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. 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 these drawings without paying creative labor.

[0018] Figure 1 A schematic diagram of the structure of a pole piece provided in an embodiment of the utility model;

[0019] Figure 2 A schematic diagram of the structure of the pole ear provided in an embodiment of the utility model;

[0020] Figure 3 A schematic diagram of the structure of a pressing piece provided in an embodiment of the utility model;

[0021] Figure 4 A schematic diagram of the structure of a pressing piece and a matching piece provided in an embodiment of the utility model;

[0022] Figure 5 Another structural schematic diagram of the pressing piece and the matching piece provided in the embodiment of the utility model.

[0023] Among them, the reference numerals in the figure are:

[0024] 100, pole piece; 10, pole ear; 20, current collector;

[0025] 11. first groove; 12. first protrusion; 200. pressing piece;

[0026] 300, matching piece; 210, boss; 310, second groove. DETAILED DESCRIPTION

[0027] The embodiments of the present invention are described in detail below, and 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 intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0028] Reference throughout the specification to "one embodiment" or "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present application. Thus, when the phrases "in one embodiment" or "in some embodiments" appear in various places throughout the specification, not all references are to the same embodiment. Furthermore, in one or more embodiments, the particular features, structures, or characteristics may be combined in any suitable manner.

[0029] In the description of the present invention, it should be understood that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply 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 a limitation on the present invention.

[0030] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features.

[0031] In the present invention, unless otherwise clearly specified and limited, the terms "install", "connect", "connect", "fix" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0032] The pole piece 100 and the indentation device in the embodiment of the utility model are now described.

[0033] For the convenience of description, the width direction of the current collector 20 is defined as the front-to-back direction, the length direction of the current collector 20 is defined as the left-right direction, and the thickness direction of the current collector 20 is defined as the up-down direction.

[0034] Please refer to Figure 1 The pole piece 100 provided in the present application includes a current collector 20 and a pole ear 10. At least one pole ear 10 is provided on one side of the current collector 20 in the first direction. At least a portion of the pole ear 10 is recessed to form a first groove 11. The first groove 11 extends along the first direction. Specifically, the pole ear 10 is provided on the front side of the current collector 20. A portion of the pole ear 10 is recessed along the thickness direction of the current collector 20, that is, along the up-down direction to form the first groove 11.

[0035] By providing the arched first groove 11 on the pole ear 10 , the pole ear 10 is formed with an uneven surface, which is beneficial to reducing the risk of the pole ear 10 being folded or cracked when the pole piece 100 is running.

[0036] In another embodiment of the present application, please refer to Figure 1 , the first direction is the width direction of the current collector. The width direction of the current collector 20 is perpendicular to the running direction of the pole piece 100, and the first groove 11 extends along the width direction of the current collector 20, which can greatly improve the ability of the pole tab 10 to withstand lateral shear force, thereby further reducing the risk of folding and cracking of the pole tab 10, thereby improving the safety performance of the battery.

[0037] Of course, in some other embodiments, the first direction may be inclined to the thickness direction of the current collector 20 .

[0038] The pole piece 100 may be a pole piece 100 having only a single pole tab 10 , or may be a pole piece 100 having a plurality of pole tabs 10 , which is not limited herein.

[0039] In another embodiment of the present application, please refer to Figure 1, one end of the first groove 11 extends to the edge of the pole lug 10, and the other end of the first groove 11 extends to the junction of the pole lug 10 and the current collector 20. Specifically, the front end of the first groove 11 extends to the front edge of the pole lug 10, and the rear end of the first groove 11 extends to the junction of the pole lug 10 and the current collector 20. The shape of the current collector 20 is rectangular, and the junction of the pole lug 10 and the current collector 20 can be understood as the edge of the current collector 20 or the rear edge of the pole lug 10. Such a configuration allows the first groove 11 to extend to the edges of the front and rear sides of the pole lug 10 in a continuous structure, which can greatly improve the ability of the pole lug 10 to withstand lateral shear force, thereby further reducing the risk of the pole lug 10 folding and cracking.

[0040] In another embodiment of the present application, please refer to Figure 1 and Figure 2 , the number of the first grooves 11 is 1 to 3. Specifically, the number of the first grooves 11 may be one, two or three. In some embodiments, the tab 10 on the pole piece 100 will be welded to a conductive object. For example, in a soft-pack battery, all the positive tabs 10 on the positive pole piece 100 will be welded to one lead-out tab 10. By limiting the number of first grooves 11, the risk of the tab 10 folding or cracking when the pole piece 100 is conveyed is reduced, and the tab 10 has sufficient welding area during transfer welding to ensure the welding effect of the transfer welding of the tab 10. In addition, in fact, the number of first grooves 11 is not the more the better. Once the number of first grooves 11 is too large, it will affect the effect of the first grooves 11 on strengthening the tab 10.

[0041] In another embodiment of the present application, please refer to Figure 1 and Figure 2 , the number of the first grooves 11 is at least two, all the first grooves 11 are arranged at intervals along the second direction, the center distance L between two adjacent first grooves 11 is 1 to 5 mm, and the second direction is perpendicular to the first direction. Specifically, in this embodiment, the second direction is the length direction of the current collector 20, the first groove 11 has a center line L1, and the distance between two adjacent center lines L1 in the left and right direction is the center distance L between two adjacent first grooves 11. The center distance L can be 1mm, 2mm, 3mm, 4mm, 5mm, etc. Limiting the center distance L to 1 to 5mm can ensure that the first groove 11 fully plays its role.

[0042] In another embodiment of the present application, please refer to Figure 2, the cross section of the first groove 11 is trapezoidal. It is understandable that the first groove 11 on the pole ear 10 is formed by processing equipment, and the processing equipment may be, for example, a rolling equipment or a stamping equipment. Compared with the first groove 11 with a rectangular cross section, the first groove 11 of this invention can facilitate the pole piece 100 to be separated from the processing equipment due to its trapezoidal cross section, and can also reduce the damage caused to the pole ear 10 by the processing equipment.

[0043] In another embodiment of the present application, please refer to Figure 2 , at least part of the tab 10 is raised to form a first protrusion 12, and the first groove 11 is arranged corresponding to the first protrusion 12, and is respectively located on two opposite sides of the tab 10 to form an arch structure. Exemplarily, in this embodiment, the upper surface of the tab 10 is formed with a first groove 11, and the lower surface of the tab 10 is formed with a first protrusion 12, and the first groove 11 and the first protrusion 12 together constitute an arch structure, which can further improve the overall strength of the tab, thereby further reducing the risk of the tab folding and cracking.

[0044] Please refer to Figures 3 to 5 The present application also provides an indentation device, which includes a pressing piece 200, a mating piece 300 and a driving mechanism. The pressing piece 200 includes a main body and a plurality of bosses 210. All bosses 210 are arranged at intervals on the main body. The bosses 210 extend along a third direction, which is perpendicular to the running direction of the pole piece 100 material strip. The mating piece 300 is arranged opposite to the mating piece 300. The driving mechanism is used to drive the pressing piece 200 and / or the mating piece 300 so that the pressing piece 200 and the mating piece 300 can extrude the pole ear 10 together.

[0045] The matching piece 300 and the pressing piece 200 are arranged at intervals in the vertical direction to form an extrusion gap for the material strip of the electrode sheet 100 to pass through. When the pole tab 10 on the material strip of the electrode sheet 100 passes through the extrusion gap, the pressing piece 200 and the matching piece 300 jointly extrude the pole tab 10 under the drive of the driving mechanism, thereby forming the first groove 11 and the first protrusion 12 on the pole tab 10.

[0046] It is understandable that the driving mechanism can drive the pressing member 200 alone, can drive the matching member 300 alone, or can drive the pressing member 200 and the matching member 300 at the same time. In addition, the driving mechanism can drive the pressing member 200 and / or the matching member 300 to make a rotary motion, or can drive the pressing member 200 and / or the matching member 300 to make a linear reciprocating motion, as long as the pressing member 200 and the matching member 300 are driven by the driving mechanism to jointly extrude the tab 10, which is not limited here.

[0047] The running direction of the pole piece 100 material strip is the length direction of the pole piece 100, and the third direction is parallel to the width direction of the pole piece 100 material strip. The boss 210 extends along the third direction so that the first groove 11 and the first protrusion 12 formed on the pole ear 10 can both extend along the third direction, which can effectively improve the pole ear 10's ability to withstand lateral shear force, thereby reducing the risk of folding or cracking of the pole ear 10.

[0048] In another embodiment of the present application, the main body is cylindrical, all bosses 210 are arranged at intervals along the circumference of the main body, the third direction is the axial direction of the main body, and the driving mechanism is used to drive at least one of the pressing piece 200 and the matching piece 300 to rotate, wherein the matching piece 300 is engaged with the pressing piece 200. The axial direction of the main body is perpendicular to the running direction of the pole piece 100 material strip, so that the pressing piece 200 and the matching piece 300 will not affect the running direction of the pole piece 100 material strip when rotating, and the damage to the pole ear 10 can be reduced.

[0049] Of course, in some embodiments, please refer to Figure 4 The mating piece 300 does not need to be engaged with the pressing piece 200. At this time, the mating piece 300 is cylindrical, and a rubber layer is provided on the outer circumferential surface of the mating piece 300 to avoid damage to the pole piece 100 caused by direct squeezing of the two rigid rollers.

[0050] In another embodiment of the present application, please refer to Figure 5 The main body has a first plane, all the bosses 210 are arranged at intervals on the first plane, the matching piece 300 has a second plane arranged opposite to the first plane, and the second plane is provided with a second groove 310 for accommodating the boss 210, and the driving mechanism is used to drive at least one of the pressing piece 200 and the matching piece 300, so that the pressing piece 200 and the matching piece 300 are close to or away from each other. Specifically, in this embodiment, the cross section of the main body and the cross section of the matching piece 300 are both rectangular, the main body is located above the matching piece 300, the lower surface of the main body is the first plane, and the boss 210 is arranged on the lower surface of the main body. The upper surface of the matching piece 300 is the second plane, the second groove 310 is arranged on the upper surface of the matching piece 300, and the second groove 310 is arranged corresponding to the boss 210. At least one of the main body and the matching piece 300 is driven by the driving mechanism to perform a linear reciprocating motion in the up and down direction, so that the main body and the matching piece 300 are close to each other and away from each other, thereby forming the first groove 11 and the first protrusion 12 on the tab 10.

[0051] In another embodiment of the present application, the height of the boss 210 is 0.5-4 mm. The height of the boss 210 can be, for example, 0.5 mm, 1 mm, 1.5 mm, 2 mm, 2.5 mm, 3 mm, 3.5 mm, 4 mm, etc. In this way, on the one hand, it can be ensured that the first groove 11 strengthens the tab 10. On the other hand, if the height of the boss 210 is too high, the driving mechanism needs to provide a greater driving force. Limiting the height of the boss 210 to 0.5-4 mm can effectively reduce the risk of the boss 210 crushing the tab 10.

[0052] It is understood that when the main body is cylindrical, the height of the boss 210 is the length of the boss 210 in the radial direction of the main body. When the cross section of the main body is rectangular, the height of the boss 210 is the length of the boss 210 in the up-down direction.

[0053] In another embodiment of the present application, please refer to Figure 4 The boss 210 has two walls arranged opposite to each other, and an angle α is formed between the two walls, and the angle α ranges from 10° to 135°. Such an arrangement can satisfy the molding effect of the first groove 11 and reduce the damage caused by the boss 210 to the tab 10.

[0054] In some embodiments, a rounded corner is provided at one end of the boss 210 away from the main body to further reduce damage to the tab 10 caused by the boss 210 .

[0055] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A pole piece, characterized in that: The invention comprises a current collector (20) and a pole lug (10), wherein at least one pole lug (10) is arranged on one side of the current collector (20) in a first direction, and at least a portion of the pole lug (10) is recessed to form a first groove (11), and the first groove (11) extends along the first direction.

2. The pole piece according to claim 1, characterized in that: The first direction is the width direction of the current collector (20); One end of the first groove (11) extends to the edge of the pole lug (10), and the other end of the first groove (11) extends to the junction between the pole lug (10) and the current collector (20).

3. The pole piece according to claim 1, characterized in that: The number of the first grooves (11) is 1 to 3.

4. The pole piece according to claim 1, characterized in that: The number of the first grooves (11) is at least two, all the first grooves (11) are arranged at intervals along the second direction, the center distance L between two adjacent first grooves (11) is 1 to 5 mm, and the second direction is perpendicular to the first direction.

5. The pole piece according to claim 1, characterized in that: At least a portion of the pole lug (10) is raised to form a first protrusion (12); the first groove (11) is arranged corresponding to the first protrusion (12) and is respectively located on two opposite sides of the pole lug (10) to form an arch structure; And / or, the cross section of the first groove (11) is trapezoidal.

6. An indentation device for manufacturing a pole piece according to any one of claims 1 to 5, characterized in that: include: A pressing piece (200) comprises a main body and a plurality of bosses (210), wherein all of the bosses (210) are arranged at intervals on the main body, and the bosses (210) extend along a third direction, wherein the third direction is perpendicular to the running direction of the pole piece (100) material strip; A matching piece (300), arranged opposite to the matching piece (300); A driving mechanism is used to drive the pressing piece (200) and / or the matching piece (300) so that the pressing piece (200) and the matching piece (300) can jointly extrude the pole ear (10).

7. The indentation device according to claim 6, characterized in that: The main body is cylindrical, all the bosses (210) are arranged at intervals along the circumference of the main body, the third direction is the axial direction of the main body, and the driving mechanism is used to drive at least one of the pressing piece (200) and the matching piece (300) to rotate, wherein the matching piece (300) is engaged with the pressing piece (200), or the matching piece (300) is cylindrical and has a rubber layer on its surface.

8. The indentation device according to claim 6, characterized in that: The main body has a first plane, and all the bosses (210) are arranged at intervals on the first plane. The matching piece (300) has a second plane arranged opposite to the first plane, and the second plane is provided with a second groove (310) for accommodating the bosses (210). The driving mechanism is used to drive at least one of the pressing piece (200) and the matching piece (300) so that the pressing piece (200) and the matching piece (300) are moved closer to or farther away from each other.

9. The indentation device according to any one of claims 6 to 8, characterized in that: The height of the boss (210) is 0.5-4 mm.

10. The indentation device according to any one of claims 6 to 8, characterized in that: The boss (210) has two wall surfaces that are arranged opposite to each other, and an angle α is formed between the two wall surfaces. The angle α ranges from 10° to 135°.

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