Method and device for locally flattening a full-tab battery core

Abstract

The present invention provides a method and device for locally flattening a full-tab battery core. A method for locally flattening a full-tab battery core includes: fixing the core; moving the flattening head and the core relative to each other until there is a dislocation between the end face of the flattening head and the end face of the core; moving the flattening head from the outer circumference of the core towards the center of the circle, and laminating and flattening each layer of tabs on the end face of the core towards the center of the circle. The method for locally flattening a full-tab battery core provided by the present invention, by having a dislocation between the end face of the flattening head and the end face of the core, and moving the flattening head from the outer circumference of the core towards the center of the circle, laminates and flattens each layer of tabs on the end face of the core towards the center of the circle, achieving local flattening to press and flatten the tabs one by one from the outside to the inside, enabling adjacent tabs to come into contact with each other, improving the current collection ability of the core and reducing the internal resistance of the core.

Description

Technical Field

[0001] The present invention relates to the technical field of battery manufacturing, and particularly to a method and device for locally flattening a full-tab battery core. Background Art

[0002] For a full-tab structured battery, when coating the positive and negative current collectors, an empty foil area is left at the edge. After winding, the empty foil area is flattened, and then a current collector plate is welded to the flattened area, and the current collector plate is further welded to the housing and the cap. In this structure, the entire positive and negative current collectors are used as the positive and negative tabs to directly lead out the current, effectively reducing the internal resistance of the battery. Among them, the tab flattening process is to press down the originally vertical tabs so that the tabs contact each other, playing a better current collection role. After flattening, the tabs are on the same plane, facilitating the welding of the current collector plate.

[0003] Currently, there are mainly two types of flattening techniques. One is mechanical flattening: the flattening head rotates and simultaneously moves towards the plane to be flattened, pressing down and flattening the tabs. The other is ultrasonic flattening: the ultrasonic flattening head moves towards the plane to be flattened, pressing down and flattening the tabs.

[0004] The above two flattening methods have the following defects:

[0005] 1. Both flatten the tabs by axial feeding. The disadvantage of this method is that the directions of pressing down the tabs are inconsistent, and there are often pit defects on the flattened plane, affecting welding; the core electrode sheets, especially the outer electrode sheets, are prone to deformation, affecting the battery cycle performance;

[0006] 2. For ultrasonic flattening, the ultrasonic waves are likely to break the tabs, especially the positive aluminum foil. The debris entering the battery will affect the safety performance;

[0007] 3. The plane after the existing mechanical flattening basically has no gap, affecting the battery liquid injection efficiency, and it is extremely prone to the situation of poor electrolyte infiltration, affecting the battery performance. Summary of the Invention

[0008] The present invention provides a method and device for locally flattening a full-tab battery core, aiming to solve the defects in the prior art that the flattening directions of ultrasonic flattening and mechanical flattening are inconsistent, the flattening quality is poor, and the overall performance of the battery is affected. The flattening head moves from the outer circumference of the core to the center of the circle, and each layer of tabs on the end face of the core pressed by the flattening head is laminated and flattened towards the center of the circle, so that the flattening direction of the tabs is always consistent without causing distortion and depression, ensuring the flattening quality and improving the overall performance of the battery.

[0009] The present invention provides a method for locally flattening a full-tab battery core, including:

[0010] Fixing the core;

[0011] The flattening head and the core move relative to each other until there is a dislocation between the end face of the flattening head and the end face of the core;

[0012] The flattening head moves from the outer circumference of the core towards the center, and laminates and flattens each layer of tabs on the end face of the core towards the center direction.

[0013] According to the method for locally flattening the full-tab battery core provided by the present invention, the dislocation distance between the end face of the flattening head and the end face of the core is greater than or equal to 3 times the spacing between the tabs.

[0014] According to the method for locally flattening the full-tab battery core provided by the present invention, the step of the flattening head and the core moving relative to each other includes:

[0015] The flattening heads placed at both ends of the core move towards the core in opposite axial directions.

[0016] According to the method for locally flattening the full-tab battery core provided by the present invention, the step of the flattening head moving from the outer circumference of the core towards the center includes:

[0017] The flattening heads in all directions converge towards the center simultaneously from the same circumference;

[0018] The flattening heads move until they contact each other.

[0019] According to the method for locally flattening the full-tab battery core provided by the present invention, it further includes:

[0020] The flattening heads move away from the core;

[0021] The flattening heads move back radially.

[0022] The present invention also provides a local flattening device for performing the above method for locally flattening the full-tab battery core, including: a flattening mounting disc and flattening heads, the flattening heads are mounted on the flattening mounting disc, and the flattening heads can move towards the center along the flattening mounting disc,

[0023] The flattening mounting disc can move axially, and the flattening heads are used to flatten the tabs on the core.

[0024] According to the local flattening device provided by the present invention, the length of the flattening heads is greater than or equal to the radius of the core.

[0025] According to the local flattening device provided by the present invention,

[0026] The interior of the flattening mounting disc includes a large bevel gear, a chute is opened on the exterior of the flattening mounting disc, and the large bevel gear includes an Archimedes spiral groove,

[0027] The rubbing flat head is provided with meshing teeth, the Archimedes spiral groove meshes with the meshing teeth, and the rubbing flat head is placed in the sliding groove.

[0028] According to the partial rubbing and flattening device provided by the present invention, a sliding rail is installed on the rubbing and flattening mounting disc, and the rubbing flat head moves centripetally on the sliding rail.

[0029] According to the partial rubbing and flattening device provided by the present invention, it further includes a core clamping device, and the center line of the core clamping device coincides with the center line of the rubbing and flattening mounting disc.

[0030] The core clamping device is used to clamp the core.

[0031] In the partial rubbing and flattening method of the all-tab battery core provided by the present invention, there is a dislocation between the end face of the rubbing flat head and the end face of the core. The rubbing flat head moves from the outer circumference of the core to the center of the circle, and each layer of tabs on the end face of the core is stacked and rubbed flat towards the center of the circle, achieving partial rubbing and flattening so that the tabs are pressed down and rubbed flat one by one from the outside to the inside. Adjacent tabs can all be in contact with each other, improving the current collection ability of the core and reducing the internal resistance of the core.

[0032] The tabs only converge and collapse towards the inside of the core where the rubbing flat head presses, which can avoid the outermost pole piece from being deformed by force, thereby improving the cycle performance of the battery; the remaining unrubbed parts are all upright and in a non-contact state with each other, improving the liquid injection efficiency, reducing the equipment investment, and reducing the cost.

[0033] Furthermore, the partial rubbing and flattening device provided by the present invention can execute the above partial rubbing and flattening method of the all-tab battery core, so it also has the advantages of the above partial rubbing and flattening method of the all-tab battery core. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0035] Figure 1 is one of the flow charts of the partial rubbing and flattening method of the all-tab battery core provided by the present invention;

[0036] Figure 2 is the schematic diagram of the dislocation state of the partial rubbing and flattening device of the all-tab battery core provided by the present invention;

[0037] Figure 3 is the second flow chart of the partial rubbing and flattening method of the all-tab battery core provided by the present invention;

[0038] Figure 4It is the third flowchart of the method for locally flattening the full-tab battery core provided by the present invention;

[0039] Figure 5 It is a schematic diagram of the initial state of the device for locally flattening the full-tab battery core provided by the present invention;

[0040] Figure 6 It is a schematic diagram after the tabs on the end face of the core are flattened provided by the present invention;

[0041] Figure 7 It is one of the schematic diagrams of the end face of the flattening head of the device for locally flattening the full-tab battery core provided by the present invention;

[0042] Figure 8 It is the second schematic diagram of the end face of the flattening head of the device for locally flattening the full-tab battery core provided by the present invention;

[0043] Reference numerals:

[0044] 100: Flattening mounting disc; 200: Flattening head; 300: Core;

[0045] 301: Core clamping device; 302: Tab; 310: Flattening superposition area;

[0046] 320: Unflattened vertical area; 201: End; 202: First end face;

[0047] 303: Second end face. Detailed implementation manners

[0048] To make the objectives, technical solutions and advantages of the present invention clearer, the technical solutions in the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the present invention. Apparently, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present invention without creative efforts shall fall within the protection scope of the present invention.

[0049] In the description of the embodiments of the present invention, it should be noted that the orientation or positional relationships indicated by the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. are based on the orientation or positional relationships shown in the drawings, and are only for the convenience of describing the embodiments of 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 thus should not be construed as limiting the embodiments of the present invention. In addition, the terms "first", "second", and "third" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance.

[0050] In the description of the embodiments of the present invention, it should be noted that unless otherwise clearly specified and limited, the terms "connected" and "coupled" 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 directly connected or indirectly connected through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the present invention can be understood according to specific situations.

[0051] In the description of this specification, the descriptions referring to terms such as "one embodiment", "some embodiments", "example", "specific example", or "some examples" mean that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the embodiments of the present invention. In this specification, the schematic descriptions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0052] The following will describe the embodiments of the present invention in conjunction with Figures 1 to 8 , it should be understood that the following is only a schematic embodiment of the present invention and does not limit the present invention.

[0053] As Figure 1 The present invention provides a method for locally flattening a full-tab battery core, including:

[0054] S1: Fix the core 300;

[0055] S2: The flattening head 200 and the core 300 move relative to each other until there is a dislocation between the first end face 202 of the flattening head 200 and the second end face 303 of the core 300;

[0056] S3: The flattening head 200 moves from the outer circumference of the core 300 towards the center of the circle, and laminates and flattens each layer of tabs 302 on the second end face 303 of the core 300 that the flattening head 200 has pressed towards the center of the circle.

[0057] As Figure 2 shown, for step S2, the flattening head 200 and the core 300 move relative to each other until there is a dislocation between the first end face 202 of the flattening head 200 and the second end face 303 of the core 300. Specifically, the first end face 202 of the flattening head 200 and the second end face 303 of the core 300 are opposite to each other.

[0058] Among them, the relative movement of the flattening head 200 and the core 300 means that the flattening head 200 moves towards the direction close to the core 300, or the core 300 moves towards the direction close to the flattening head 200, or both move towards each other.

[0059] In addition, the dislocation of the first end face 202 and the second end face 303, that is, during the relative movement of the flattening head 200 and the core 300, the first end face 202 and the second end face 303 are first flush in the same plane, and then, continue to move relatively along the original direction, forming a dislocation between the first end face 202 and the second end face 303, forming a dislocation distance H.

[0060] In other words, when the core 300 does not move and the flattening head 200 moves towards the direction close to the core 300, first the first end face 202 and the second end face 303 are first flush in the same plane, and then, the flattening head 200 continues to move, and the first end face 202 crosses the second end face 303, forming a dislocation.

[0061] Furthermore, in an embodiment of the present invention, the dislocation distance H between the first end face 202 of the flattening head 200 and the second end face of the core 300 is greater than or equal to three times the pitch between the tabs 302.

[0062] In an alternative embodiment of the present invention, the step of the relative movement of the flattening head 200 and the core 300 in step S2 includes:

[0063] The flattening heads 200 placed at both ends of the core 300 move towards the core 300 along opposite axial directions.

[0064] As Figure 3 shown, in an alternative embodiment of the present invention, the step of the flattening head moving from the outer circumference of the core to the center in step S3 includes:

[0065] S11: The flattening heads 200 in all directions converge towards the center simultaneously from the same circumference;

[0066] S12: The flattening heads 200 move until they contact each other.

[0067] As Figure 4 shown, in a specific embodiment of the present invention, the method for locally flattening the full-tab battery core further includes:

[0068] S4: The flattening head 200 moves away from the core 300;

[0069] S5: The flattening head 200 moves back along the radial direction.

[0070] Specifically, after the flattening head 200 finishes flattening the tab 302, it first moves axially away from the second end face 303, and then radially returns each flattening head 200 to its original position. Wait for the next flattening process.

[0071] As Figure 5 shown, the present invention provides a device for locally flattening a full-tab battery core, including: a flattening mounting disc 100 and flattening heads 200. The flattening heads 200 are mounted on the flattening mounting disc 100, and the flattening heads 200 can move centripetally along the flattening mounting disc 100.

[0072] Among them, the flattening mounting disc 100 can move axially, and the flattening heads are used to flatten the tabs 302 on the core 300.

[0073] Specifically, as Figure 6 shown, there are layers of tabs 302 at both ends of the core 300. The flattening heads 200 move from the outer circumference of the core 300 towards the center of the circle. The tabs 302 at the position of the core 300 passed by the flattening heads 200 are flattened. The flattening direction of each layer of tabs 302 is centripetal, and the layers of tabs 302 overlap each other.

[0074] Therefore, two regions are formed on the end face of the core 300, one is the flattened and superimposed region 310, and the other is the unflattened vertical region 320. Inside the flattened and superimposed region 310 are the layers of flattened and superimposed tabs 302; inside the unflattened vertical region 320 are the tabs 302 that are not contacted by the flattening heads 200 and remain in their original state, and there are vertical gaps between adjacent tabs 302.

[0075] As Figure 3 shown, in an embodiment of the present invention, the length L of the flattening head 200 is greater than or equal to the radius of the core 300. It can achieve a better flattening effect, with radial full force application, preventing incomplete flattening of the tabs 302.

[0076] Continue to refer to Figure 5 , in an embodiment of the present invention, the device for locally flattening a full-tab battery core further includes a core clamping device 301, and the center line of the core clamping device 301 coincides with the center line of the flattening mounting disc 100. To achieve a better alignment effect.

[0077] Among them, the core clamping device 301 is used to clamp the core 300.

[0078] Continue to refer to Figure 5 , in another embodiment of the present invention, the device for locally flattening a full-tab battery core includes two sets of flattening mounting discs 100 and flattening heads 200. The two sets of flattening mounting discs 100 and flattening heads 200 are placed opposite to each other and are respectively located at both ends of the core clamping device 301.

[0079] In other words, the core clamping device 301 clamps the middle part of the core 300, and both ends of the core 300 are respectively placed at both ends of the core clamping device 301. Each group of flattening mounting discs 100 and flattening heads 200 respectively flatten the tab 302 at both ends of the core 300.

[0080] Of course, each group of flattening mounting discs 100 and flattening heads 200 can flatten the tabs 302 at both ends of the core 300 simultaneously, or can also flatten the tabs 302 at both ends of the core 300 separately.

[0081] It should be understood that the center lines of each group of flattening mounting discs 100 and the core clamping device 301 coincide. That is, the center lines of each group of flattening mounting discs 100, the core clamping device 301, and the core 300 coincide.

[0082] In addition, in an alternative embodiment of the present invention, the inside of the flattening mounting disc 100 includes a large bevel gear, a chute is opened on the outside of the flattening mounting disc 100, and the large bevel gear includes an Archimedean spiral groove.

[0083] Among them, the flattening head 200 is provided with meshing teeth, the Archimedean spiral groove meshes with the meshing teeth, and the flattening head 200 is placed in the chute.

[0084] Furthermore, in the embodiment of the present invention, the inside of the flattening mounting disc 100 further includes a small bevel gear, the small bevel gear drives the large bevel gear to rotate, and the large bevel gear drives the flattening head 200 to move centripetally along the chute.

[0085] Specifically, a chute is radially opened on the outside of the flattening mounting disc 100, a large bevel gear is installed inside the flattening mounting disc 100, and an Archimedean spiral groove is opened on one side of the large bevel gear.

[0086] The chute is a through groove, exposing the Archimedean spiral groove. The flattening head 200 is placed in the chute, and the meshing teeth of the flattening head 200 cooperate with the Archimedean spiral groove and move radially under the guidance of the chute.

[0087] The small bevel gear meshes and drives with the other side of the large bevel gear. The small bevel gear can be driven to rotate by a servo motor, thereby driving the rotation of the large bevel gear and realizing the radial movement of the flattening head 200.

[0088] In another alternative embodiment of the present invention, a slide rail is installed on the flattening mounting disc 100, and the flattening head 200 moves centripetally on the slide rail.

[0089] Specifically, the flattening mounting disc 100 is installed with a slide rail along the radial direction, and the flattening head 200 cooperates with the slide rail to slide. The flattening head 200 can be driven to move radially on the slide rail by a cylinder.

[0090] As Figure 7 and Figure 8 shown, in an embodiment of the present invention, the flattening heads 200 are evenly distributed on the flattening mounting disc 100 at equal angles.

[0091] In this embodiment, it can be trisected or quadrisected, or can be set according to the flattening requirements of the tabs 302 as needed, so as to obtain a uniform flattening effect of the tabs 302.

[0092] Because, during the actual flattening process, the junction between the flattened overlapping area 310 and the unflattened vertical area 320 will be distorted by the action of force. Especially, the gap between the tabs in the unflattened vertical area 320 becomes narrower. Therefore, equidistant flattening can ensure a larger tab gap in the unflattened vertical area 320.

[0093] Of course, it should be understood that non-uniform division will not affect the use effect of flattening the tabs of the core 300. Local flattening can be achieved.

[0094] Referring to Figure 8 , in an alternative embodiment of the present invention, the flattening head 200 is strip-shaped, and the end 201 is arc-shaped.

[0095] The ends 201 of all the flattening heads 200 are all oriented towards the center of the flattening mounting disc 100.

[0096] The local flattening method for the full-tab battery core provided by the present invention has the end face of the flattening head misaligned with the end face of the core. The flattening head moves from the outer circumference of the core towards the center of the circle, and laminarly flattens each layer of tabs on the end face of the core towards the center of the circle, achieving local flattening so that the tabs are successively pressed down and flattened from the outside to the inside, and adjacent tabs can all contact each other, improving the current collection ability of the core and reducing the internal resistance of the core;

[0097] The tabs only converge and collapse towards the inside of the core where the flattening head presses, which can avoid the deformation of the outermost pole piece due to force, thereby improving the cycle performance of the battery; the remaining unflattened parts are all upright and in a non-contact state with each other, improving the liquid injection efficiency, reducing the equipment investment, and lowering the cost.

[0098] Furthermore, the flattening device provided by the present invention can execute the above local flattening method for the full-tab battery core, so it also has the advantages of the above local flattening method for the full-tab battery core.

[0099] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments or perform equivalent replacements for some of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A method for locally flattening a full-tab battery core, characterized in that, it includes: Fixing the battery core; The flattening head and the battery core move relative to each other until there is a dislocation between the end face of the flattening head and the end face of the battery core; The step of the flattening head and the battery core moving relative to each other includes: The flattening heads placed at both ends of the battery core move along the axial opposite directions towards the battery core; The flattening head moves from the outer circumference of the battery core towards the center of the circle, and laminates and flattens each layer of tabs on the end face of the battery core towards the center of the circle; The step of the flattening head moving from the outer circumference of the battery core towards the center of the circle includes: The flattening heads in all directions move radially from the same circumference and converge towards the center; The flattening heads move until they contact each other.

2. The method for locally flattening a full-tab battery core according to claim 1, characterized in that, The dislocation distance between the end face of the flattening head and the end face of the battery core is greater than or equal to 3 times the spacing between the tabs.

3. The method for locally flattening a full-tab battery core according to claim 1, characterized in that, It further includes: The flattening head moves away from the battery core; The flattening head moves back radially.

4. A local flattening device for performing the method for locally flattening a full-tab battery core according to any one of claims 1 to 3, characterized in that, it includes: A flattening mounting disc and a flattening head, the flattening head is mounted on the flattening mounting disc, and the flattening head can move towards the center along the flattening mounting disc, The flattening mounting disc can move axially, and the flattening head is used to flatten the tabs on the battery core.

5. The local flattening device according to claim 4, characterized in that, The length of the flattening head is greater than or equal to the radius of the battery core.

6. The local flattening device according to claim 4, characterized in that, The inside of the flattening mounting disc includes a large bevel gear, a chute is opened on the outside of the flattening mounting disc, and the large bevel gear includes an Archimedes spiral groove, The flattening head is provided with meshing teeth, the Archimedes spiral groove meshes with the meshing teeth, and the flattening head is placed in the chute.

7. The local flattening device according to claim 4, characterized in that, A slide rail is mounted on the flattening mounting disc, and the flattening head moves towards the center on the slide rail.

8. The local flattening device according to claim 4, characterized in that, It further includes a battery core clamping device, the center line of the battery core clamping device coincides with the center line of the flattening mounting disc, The battery core clamping device is used to clamp the battery core.

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