Lithium battery laser welding auxiliary device

Abstract

The utility model discloses a lithium battery laser welding auxiliary device which comprises a chassis and a clamping mechanism arranged on the chassis and used for clamping a battery side, the clamping mechanism comprises a first clamping unit and a second clamping unit, the clamping direction of the first clamping unit is perpendicular to the clamping direction of the second clamping unit, and the clamping direction of the second clamping unit is perpendicular to the clamping direction of the first clamping unit. The distance between the upper edge of a clamping part of the clamping mechanism and a battery shell opening is 2-4mm, and the clamping part wraps and clamps the battery on three side surfaces of the battery; and a pressure head is arranged above the clamping mechanism and is used for pressing the top of the battery cover plate in the vertical direction. According to the utility model, the risk that the battery shell is scratched can be reduced; the shell can be in a clamped state and is not easy to deform due to heating, so that the shell is prevented from being poorly swelled; the upper edge, close to the edge of the battery shell opening, of the clamping part clamps the battery shell opening, and the problems that in the using process of an existing tool, sand holes are easily caused, poor liquid leakage is caused by deviation of a welding track easily, and short circuit in a battery is poor due to burning of a diaphragm easily can be solved.

Description

Technical Field

[0001] The utility model relates to the technical field of battery welding, in particular to a lithium battery laser welding auxiliary device. Background Art

[0002] One of the biggest technical issues of power batteries is their safety, so the peripheral welding process in the production process is very important. The principle of peripheral welding is to use the high energy, high stability, linearity and other characteristics of laser to instantly melt the materials to be welded, let them recombine and cool, so as to achieve the purpose of sealing the battery shell and battery cover.

[0003] The existing lithium battery laser-assisted welding is made of aluminum, which can easily scratch the battery shell when loading and unloading the battery, resulting in poor battery appearance; after the battery is clamped and welded, the fixed baffle and the pressing block in contact with the battery are small in area and cannot be fully in contact with the battery shell. The uncontacted shell part is easily swollen and deformed due to heat during welding, which in turn affects the later battery packaging. In addition, the position of the battery after tightening is significantly higher than the height of the pressing block and the fixed baffle. Since the shell mouth welding position is significantly higher than the clamping tooling, a gap will be left due to the loose clamping of the battery shell mouth. At this time, the laser can easily penetrate the gap and directly burn the diaphragm, causing a battery short circuit. Moreover, the poor consistency of the battery with an unclamped shell mouth can easily cause trajectory deviation and the appearance of molten pool sand holes (small holes formed by gas or impurities inside or on the surface of the casting), which can cause battery leakage. Utility Model Content

[0004] The purpose of the utility model is to overcome the deficiencies and defects of the prior art and to provide a lithium battery laser welding auxiliary device.

[0005] A lithium battery laser welding auxiliary device comprises a chassis and a clamping mechanism arranged on the chassis for clamping a battery on the battery side, the clamping mechanism comprises a first clamping unit and a second clamping unit, the clamping direction of the first clamping unit is perpendicular to the clamping direction of the second clamping unit, the upper edge of the clamping part of the clamping mechanism is 2-4mm away from the battery shell opening, the battery is wrapped and clamped on three sides of the battery, and a battery access port is reserved on the short side of the battery for non-wrapping clamping; a pressure head is arranged above the clamping mechanism for pressing the top of the battery cover in the vertical direction.

[0006] Wherein, the first clamping unit includes a first clamping part, which includes a pair of first clamping blocks made of metal arranged opposite to each other, and a first lining layer made of plastic material is arranged under each of the first clamping blocks, and the area of ​​the first lining layer is larger than the area of ​​the first clamping block.

[0007] Among them, one of the first clamping blocks and the corresponding first lining layer are arranged on the inner side surface of the first clamping plate that is driven to move, and another of the first clamping blocks and the corresponding first lining layer are arranged on the inner side surface of the first reference plate.

[0008] The outer side surface of the first clamping plate is connected to the first clamping cylinder via a first cylinder fixing plate, the first reference plate is vertically arranged on the chassis, and the first cylinder fixing plate is fixed on the chassis.

[0009] Among them, the second clamping unit includes a second clamping part, which includes a pair of second clamping blocks made of metal, a second lining layer made of plastic is arranged below the inner side of one of the second clamping blocks, and the other second clamping block is arranged on the inner side surface of the rotatable second clamping plate; the area of ​​the second lining layer is larger than the area of ​​the second clamping block.

[0010] The second lining layer and the second clamping block thereon are arranged on the inner side surface of the second reference plate, and the second clamping plate is connected to a second clamping cylinder.

[0011] Wherein, the second reference plate is vertically arranged on the chassis.

[0012] Wherein, the second clamping cylinder is a rotary clamping cylinder, which is used to drive the second clamping plate to rotate and move linearly.

[0013] Wherein, the second clamping plate is an L-shaped plate.

[0014] Wherein, the second clamping cylinder is fixed on a second cylinder fixing plate, the second cylinder fixing plate is located on the outer side of the second reference plate, and the second cylinder fixing plate is arranged on the chassis.

[0015] The utility model is designed such that the distance between the upper edge of the clamping part of the clamping mechanism and the battery shell opening is 2-4mm, the battery is wrapped and clamped on three sides of the battery, and a battery access opening is reserved on the short side of the battery for non-wrapping clamping. The device has a stronger wrapping property for the battery, is more stable and more consistent during the welding process, and is easier to ensure the welding quality of the battery.

[0016] In addition, the auxiliary welding device of the present invention directly contacts the battery shell by arranging a non-metallic lining layer on the side of the clamping part that contacts the battery, thereby eliminating the risk of scratches caused by direct contact between metal and metal; by providing the lining layer, the contact area with the battery is increased, and the battery is clamped on three sides in a wrapped manner. In this way, even if the shell is heated during the welding process, the shell is in a clamped state and is not easily deformed by heat, thereby preventing the shell from bulging badly; in addition, the battery shell mouth is clamped close to the battery shell mouth by the clamping part and the three sides are wrapped and clamped, thereby solving the problems of easy formation of sand holes, easy deviation of the welding track causing poor leakage, and easy burning of the diaphragm causing poor internal short circuit of the battery during the use of the existing tooling. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is the axonometric structure diagram of the lithium battery laser welding auxiliary device of the utility model

[0018] Figure 2 This is a partial enlarged view of the lithium battery laser welding auxiliary device of the utility model. DETAILED DESCRIPTION

[0019] The present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0020] like Figures 1 to 2 As shown, a lithium battery laser welding auxiliary device according to an embodiment of the utility model comprises a chassis 13 and a clamping mechanism arranged on the chassis for clamping the battery side to the battery, the clamping mechanism comprises a first clamping unit and a second clamping unit, the clamping direction of the first clamping unit is perpendicular to the clamping direction of the second clamping unit, the distance between the upper edge of the clamping part of the clamping mechanism and the battery shell opening is within a predetermined very small distance threshold, and the distance threshold is 2-4mm, the clamping part of the clamping mechanism can wrap around the battery on three sides of the battery, and reserve a battery access opening on the short side of the battery for non-wrapping clamping, that is, the battery 1 is taken and placed on the short side of the battery, and is clamped only at the upper end near the battery shell opening; a pressure head 9 is arranged above the clamping mechanism for vertically pressing the top of the battery cover 100 of the battery 1 (such as a square battery) to be welded.

[0021] The clamping mechanism of the structure of the device of the utility model has a predetermined distance threshold of 2-4 mm between the upper edge of the clamping part and the battery shell opening. The clamping part of the clamping mechanism wraps and clamps the battery on three sides of the battery, which has a stronger wrapping property for the battery 1, is more stable during the welding process, and has higher consistency.

[0022] In an optional embodiment, the first clamping unit includes a first clamping portion, which includes a pair of first clamping blocks 3 made of metal arranged relatively to each other, and a first lining layer 2 made of plastic is arranged under each first clamping block 3, and the area of ​​the first lining layer 2 is larger than the area of ​​the first clamping block 3. The first clamping block 3 is used to clamp a small area of ​​the long side of the battery near the shell opening, and the first lining layer 2 is used to clamp other large areas of the long side except for the predetermined position of the shell opening clamped by the first clamping block 3.

[0023] Preferably, the first inner lining layer is made of POM material. By using a first inner lining layer of non-metallic plastic material in contact with the first surface of the long side of the battery, the surface scratch of the battery shell can be effectively prevented. In an optional embodiment, the first clamping block and the pressure head are made of high temperature resistant and fast heat conductive brass material to avoid melting the workpiece while the laser melts the shell cover, and can quickly conduct the heat of the welding position.

[0024] Among them, one of the first clamping blocks 3 and its corresponding first lining layer 2 are arranged on the inner side of the first clamping plate 5 that is driven and movable, and another of the first clamping blocks 3 and its corresponding first lining layer 2 are arranged on the inner side of the first reference plate 11.

[0025] In an optional embodiment, the outer side surface of the first clamping plate 5 is connected to the first clamping cylinder 4 via the first cylinder fixing plate 6 , the first reference plate 11 is vertically arranged on the chassis 13 , and the first cylinder fixing plate 6 is fixed on the chassis 13 .

[0026] In one embodiment, the second clamping unit includes a second clamping portion, which includes a pair of second clamping blocks 14 made of metal, a second inner lining layer 15 made of plastic is arranged below the inner side of one of the second clamping blocks, and another second clamping block (not shown or exposed, covered by the second clamping plate 8) is arranged on the inner side of the rotatable second clamping plate 8; the area of ​​the second inner lining layer is larger than the area of ​​the second clamping block. The second clamping block 14 is used to clamp a small area at the shell opening of the short side of the battery, and the second inner lining layer 15 is used to clamp other large areas of the short side except the predetermined position of the shell opening clamped by the second clamping block 14.

[0027] Preferably, the second lining layer 15 is made of POM material. By adopting a first lining layer of non-metallic plastic material in contact with the second surface of the short side of the battery, the problem of scratches on the surface of the battery shell can be effectively prevented. In an optional embodiment, the second clamping block 14 is made of high-temperature resistant and heat-conductive brass material to avoid laser melting of the shell cover and the workpiece at the same time, and can quickly conduct the heat of the welding position.

[0028] In one embodiment, the second lining layer 15 and the second clamping block 14 thereon are arranged on the inner side of the second reference plate 10, and the second clamping plate 8 is connected to the second clamping cylinder 7. The second reference plate 10 is arranged vertically on the chassis.

[0029] In one embodiment, the second clamping cylinder 7 is a rotary clamping cylinder, which is used to drive the second clamping plate 8 to rotate and move linearly. Preferably, the second clamping plate is an L-shaped plate.

[0030] In one embodiment, the second clamping cylinder 7 is fixed on a second cylinder fixing plate (not shown or exposed, and blocked by the second reference plate 11), the second cylinder fixing plate is located on the outside of the second reference plate 11, and the second cylinder fixing plate 17 is arranged on the chassis 13.

[0031] In addition, a corresponding groove 16 is formed on one side of the first clamping unit, that is, on the side for taking and placing the battery, so that the employee can take and place the battery conveniently, that is, conveniently put the battery into the device for clamping or taking it out, which can increase the production efficiency to a certain extent. Specifically, a groove 16 is formed at the corresponding position of the first clamping plate of the first clamping unit and the first inner lining layer inside thereof and the first cylinder fixing plate, and a groove 16 is also formed at the corresponding device of the first reference plate and the second inner lining layer inside thereof, see Figure 1 shown.

[0032] like Figure 2 As shown, after the battery 1 is clamped and fixed, the distance between the welding position of the battery shell mouth and the edge of the clamping plate is reduced to a minimum of only 2 mm without affecting the molten pool welding. Sufficient external force can be provided by the cylinder to act on the welding position of the battery shell mouth, thereby ensuring that the battery shell mouth can be 100% clamped, eliminating the gaps between the battery shell mouths, and ensuring the consistency of the shell cover fit, thereby not only reducing the proportion of sand holes and trajectory deviations, but also preventing the laser from passing through the battery shell mouth to burn the internal short circuit of the diaphragm.

[0033] In addition, corresponding support blocks 12 are provided on the outer sides of the first clamping plate and the first reference plate for reinforcement and support, thereby effectively avoiding the battery skew caused by the interaction force.

[0034] When welding, place the battery 1 in Figure 1 The right side of the device shown is placed into the device, and the button is started. The second clamping cylinder 7 is actuated, driving the second clamping plate 8 to rotate and contract, so that the second clamping plate and the second reference plate 10 interact with each other to clamp the short side of the battery, and then the first clamping cylinder 4 extends out to push the first clamping plate 5 to interact with the first reference plate 11 to clamp the long side of the battery; after the battery is clamped, the pressure head 9 is actuated by the clamping cylinder to contact the upper end surface of the battery cover plate, thereby fixing the battery in the device.

[0035] Among them, when welding the battery, the welding method can be to weld the four sides of the battery separately. The welding laser head is installed on the X-axis, Y-axis, and Z-axis modules. When welding, the three axes cooperate with each other to complete the welding action based on the set starting point position, welding speed, focal length and other parameters. After the battery clamping action is completed, the PLC signal is triggered to perform the welding action. First, the laser head moves to the welding starting position of the first side of the four sides, and then the laser is triggered to emit laser, the nitrogen valve is opened, and welding is performed; after the laser head moves to the end position, the laser stops emitting laser, the nitrogen valve is closed, and the laser head returns to a safe position; thereafter, this welding auxiliary device is driven by the motor to rotate 90° to perform the welding state of the next side. After the welding of the four sides is completed, the laser head moves to the initial position, the two clamping cylinders are reset, the battery is released, and the battery is removed from the groove position.

[0036] After the utility model was put into production, the same employee was arranged to produce 600 batteries per day for verification experiments. After collecting data for 14 consecutive days and comparing it with the previous data, it was found that the defects such as track deviation, battery leakage, battery internal short, shell scratch and bulging were significantly reduced, and the total yield rate increased by 2.32%. The improvement not only saved material costs, but also reduced labor rework costs and improved production efficiency.

[0037] The above shows and describes the basic principle and main features of the utility model and the advantages of the utility model. For those skilled in the art, it is obvious that the utility model is not limited to the details of the above exemplary embodiments, and the utility model can be implemented in other specific forms without departing from the spirit or basic features of the utility model.

[0038] Therefore, no matter from which point of view, the embodiments should be regarded as illustrative and non-restrictive, and the scope of the present invention is limited by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims are included in the present invention.

[0039] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. Lithium battery laser welding auxiliary device, characterized in that: It includes a chassis and a clamping mechanism arranged on the chassis for clamping the battery on the battery side, the clamping mechanism includes a first clamping unit and a second clamping unit, the clamping direction of the first clamping unit is perpendicular to the clamping direction of the second clamping unit, the distance between the upper edge of the clamping part of the clamping mechanism and the battery shell opening is 2-4mm, the battery is wrapped and clamped on three sides of the battery, and a battery access port is reserved on the short side of the battery for non-wrapping clamping; a pressure head is arranged above the clamping mechanism for pressing the top of the battery cover in the vertical direction.

2. The lithium battery laser welding auxiliary device according to claim 1, characterized in that: The first clamping unit includes a first clamping portion, which includes a pair of first clamping blocks made of metal arranged opposite to each other, and a first lining layer made of plastic is arranged under each of the first clamping blocks, and the area of ​​the first lining layer is larger than the area of ​​the first clamping block.

3. The lithium battery laser welding auxiliary device according to claim 2, characterized in that: One of the first clamping blocks and the corresponding first lining layer is arranged on the inner side of the first clamping plate that is driven to move, and another of the first clamping blocks and the corresponding first lining layer is arranged on the inner side of the first reference plate.

4. The lithium battery laser welding auxiliary device according to claim 3, characterized in that: The outer side surface of the first clamping plate is connected to the first clamping cylinder through the first cylinder fixing plate, the first reference plate is vertically arranged on the chassis, and the first cylinder fixing plate is fixed on the chassis.

5. The lithium battery laser welding auxiliary device according to claim 1, characterized in that: The second clamping unit includes a second clamping part, which includes a pair of second clamping blocks made of metal, a second lining layer made of plastic is arranged below the inner side of one of the second clamping blocks, and the other second clamping block is arranged on the inner side of a rotatable second clamping plate; the area of ​​the second lining layer is larger than the area of ​​the second clamping block.

6. The lithium battery laser welding auxiliary device according to claim 5, characterized in that: The second lining layer and the second clamping block thereon are arranged on the inner side surface of the second reference plate, and the second clamping plate is connected to a second clamping cylinder.

7. The lithium battery laser welding auxiliary device according to claim 6, characterized in that: The second reference plate is vertically arranged on the chassis.

8. The lithium battery laser welding auxiliary device according to claim 6, characterized in that: The second clamping cylinder is a rotary clamping cylinder, which is used to drive the second clamping plate to rotate and move linearly.

9. The lithium battery laser welding auxiliary device according to claim 5, characterized in that: The second clamping plate is an L-shaped plate.

10. The lithium battery laser welding auxiliary device according to claim 6, characterized in that: The second clamping cylinder is fixed on a second cylinder fixing plate, the second cylinder fixing plate is located outside the second reference plate, and the second cylinder fixing plate is arranged on the chassis.

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