Welding method for multi-layer tab of battery, and battery

Abstract

A welding method for a multi-layer tab (100) of a battery, and a battery. The welding method comprises the following steps: S1, using laser to perform continuous scanning welding on a multi-layer tab (100) and a part to be welded, so as to form a strip-shaped or block-shaped weld mark (300); and S2, repeating step S1, so as to form a plurality of discontinuous weld marks (300) at the joint between the multi-layer tab (100) and the part to be welded.

Description

Battery multi-layer tab welding method and battery

[0001] This disclosure claims priority to the Chinese patent application filed with the Patent Office of China on June 27, 2023, with application number 202310768357.3, and application name “Battery Multi-layer Tab Welding Method and Battery”, and the Chinese patent application filed with the Patent Office of China on June 20, 2023, with application number 202321583433.5, and application name “Battery Multi-layer Tab Welding Method and Battery”, the entire contents of which are incorporated into this disclosure by reference. Technical Field

[0002] The present disclosure relates to a battery multi-layer tab welding method and a battery. Background Art

[0003] Traditionally, ultrasonic welding is often used to weld multi-layer tabs to electrical adapters. Due to the thinness of the tabs, they are easily torn by mechanical vibration during ultrasonic welding. Furthermore, due to the size limitations of the ultrasonic welding head and welding base (oversized welding heads and welding bases are extremely susceptible to damage), the weld mark area is limited. When the weld mark area is small, the current flow area is also small, which is not conducive to the development of battery fast charging technology.

[0004] To prevent the tabs from tearing due to mechanical vibration, some technologies use quasi-continuous laser welders to weld multiple layers of tabs to electrical adapters. However, because quasi-continuous laser welders use pulsed lasers, the weld area is point-shaped and small in diameter. Even with densely distributed points, the weld area remains small, and the current flow area is small, which is still not conducive to the development of battery fast charging technology.

[0005] Summary of the Invention

[0006] Based on this, it is necessary to provide a battery multi-layer tab welding method and a battery that can avoid tab tearing and increase the weld area to increase the current flow area to address the above problems.

[0007] A method for welding multi-layer tabs of a battery, comprising the steps of:

[0008] S1: Use laser to continuously scan and weld the multi-layer tabs and the workpiece to be welded to form strip or block weld marks;

[0009] S2: Repeat step S1 to form a plurality of discontinuous weld marks at the connection between the multi-layer tab and the workpiece to be welded.

[0010] In one embodiment, step S1 includes:

[0011] The welding mark is formed by reciprocating continuous scanning or spiral continuous scanning of the laser.

[0012] In one embodiment, the laser reciprocating continuous scanning is:

[0013] The laser scans reciprocally and continuously along at least one of a square waveform, a sine waveform and a cosine waveform.

[0014] In one embodiment,

[0015] Welding positions 1 to N are preset in sequence at the connection between the multi-layer tab and the workpiece to be welded;

[0016] The two weld marks formed at adjacent welding positions are defined as a first weld mark and a second weld mark, and there is a preset time interval between the time period for welding the first weld mark and the time period for welding the second weld mark, and the preset time interval is greater than or equal to the minimum time interval between the first weld mark and the second weld mark in which there is no heat accumulation effect.

[0017] In one embodiment, the method includes:

[0018] Welding positions 1 to N are preset at the connection between the multi-layer tab and the workpiece to be welded;

[0019] Welding at the odd-numbered welding positions to form the weld marks;

[0020] Welding at the even-numbered welding positions to form the weld marks; or

[0021] Welding positions 1 to N are preset at the connection between the multi-layer tab and the workpiece to be welded;

[0022] Welding at the even-numbered welding positions to form the weld marks;

[0023] The weld marks are formed by welding at the odd-numbered welding positions.

[0024] In one embodiment, the parts to be welded are electrical adapters.

[0025] In one embodiment, the method includes:

[0026] Using a laser welding system to continuously scan and weld the multi-layer tab and the workpiece to be welded to form the weld mark;

[0027] The laser welding system includes a laser generator and a galvanometer. The galvanometer can deflect the laser emitted by the laser generator onto the multi-layer tab and the workpiece to be welded. The galvanometer can move at a preset angle so that the scanning trajectory of the laser is a continuous line pattern.

[0028] In one embodiment, the laser is a single-mode continuous laser.

[0029] In one embodiment, a laser is used to continuously scan and weld the multi-layer tabs and the workpiece to be welded in the dust removal system to form the weld mark;

[0030] The dust removal system includes a first dust removal hood and a second dust removal hood, and a storage space for accommodating the parts to be welded is formed between the first dust removal hood and the second dust removal hood; one side of the first dust removal hood and the second dust removal hood can be connected to a compressed air system, and one side of the first dust removal hood and the second dust removal hood can be connected to an exhaust dust collector; the compressed air system can blow air into the storage space, and the exhaust dust collector can extract the gas from the storage space to remove dust.

[0031] A battery comprising:

[0032] Multi-layer tabs;

[0033] An electrical adapter is laser-welded to the multi-layer tab; the connection between the electrical adapter and the multi-layer tab has a plurality of discontinuous strip or block weld marks;

[0034] Each of the weld marks is formed by reciprocating continuous scanning or spiral continuous scanning of the laser.

[0035] The battery multi-layer tab welding method and battery provided in the embodiment of the present application form strip or block-shaped weld marks on the multi-layer tabs and the parts to be welded by laser continuous scanning welding. Compared with ultrasonic laser welding, it does not generate mechanical vibration and tear the tabs. At the same time, laser continuous scanning welding can increase the weld mark area, and the welding tension and residual area are large, thereby increasing the current flow area of ​​the battery, which is beneficial to the development of battery fast charging technology. In addition, laser welding is a non-contact processing and will not cause wear like the welding seat and welding head of ultrasonic welding (the welding seat and welding head of ultrasonic welding are high-value, fragile and consumable items that need to be replaced and maintained after reaching the number of uses). It does not require frequent replacement and equipment maintenance, which reduces maintenance costs. Similarly, compared with quasi-continuous laser welding, the laser scanning trajectory is linear instead of dot-shaped, which increases the weld mark area, and the welding tension and residual area are large, thereby increasing the current flow area of ​​the battery, which is beneficial to the development of battery fast charging technology. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] FIG1 is a flow chart of a battery multi-layer tab welding method provided by one embodiment of the present application;

[0037] FIG2 is a partial structural diagram of a battery provided in one embodiment of the present application;

[0038] FIG3 is a comparison diagram of the laser scanning trajectory in the battery multi-layer tab welding method provided by an embodiment of the present application and the laser scanning trajectory in the prior art;

[0039] FIG4 is a structural diagram of a dust removal system used in the battery multi-layer tab welding method provided in this application;

[0040] FIG5 is a diagram of a laser scanning trajectory in a battery multi-layer tab welding method provided by another embodiment of the present application;

[0041] FIG6 is a diagram showing the scanning trajectory of a laser in a battery multi-layer tab welding method provided in another embodiment of the present application.

[0042] 100. Multi-layer tabs; 200. Electrical adapter; 300. Welding mark; 400. First dust cover; 500. Second dust cover; 600. Exhaust and dust removal port; 700. Throttle valve; 800. Accommodation space. DETAILED DESCRIPTION

[0043] To make the above-mentioned objects, features, and advantages of the present disclosure more clearly understood, specific embodiments of the present disclosure are described in detail below with reference to the accompanying drawings. The following description sets forth many specific details to facilitate a full understanding of the present disclosure. However, the present disclosure can be implemented in many other ways than those described herein, and those skilled in the art may make similar modifications without violating the scope of the present disclosure. Therefore, the present disclosure is not limited to the specific embodiments disclosed below.

[0044] In the description of the present disclosure, 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", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present disclosure 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 should not be understood as a limitation to the present disclosure.

[0045] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features being referred to. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. Throughout the present disclosure, "plurality" means at least two, such as two, three, etc., unless otherwise specifically defined.

[0046] In this disclosure, unless otherwise expressly specified or limited, terms such as "installed," "connected," "connect," and "fixed" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integration; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and internal communication between two components or interaction between two components, unless otherwise expressly limited. Those skilled in the art will understand the specific meanings of the above terms in this disclosure based on specific circumstances.

[0047] In the present disclosure, unless otherwise expressly specified or limited, when a first feature is "above" or "below" a second feature, it may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Furthermore, when a first feature is "above," "above," or "above" a second feature, it may mean that the first feature is directly above or diagonally above the second feature, or simply means that the first feature is at a higher level than the second feature. When a first feature is "below," "below," or "below" a second feature, it may mean that the first feature is directly below or diagonally below the second feature, or simply means that the first feature is at a lower level than the second feature.

[0048] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be an intermediate element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be an intermediate element. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only implementation methods.

[0049] Referring to FIG1 , an embodiment of the present application provides a method for welding multi-layer tabs of a battery, comprising the following steps:

[0050] S1: Using laser to continuously scan and weld the multi-layer tab 100 and the workpiece to be welded to form a strip or block weld mark 300;

[0051] When preparing a battery, the electrodes are stacked to form a bare cell, and the tabs of each electrode are overlapped to form a multi-layer tab 100 .

[0052] In some embodiments, referring to FIG2 , the part to be welded is an electrical adapter 200 (TAB sheet). Electrical adapter 200 can conduct current, output voltage and current, and serve as the positive and negative electrodes of a battery cell to connect to other battery cells or electrical appliances. Of course, in other embodiments, the type of part to be welded is not limited; for example, the part to be welded can also be a cover plate.

[0053] Continuous scanning welding means that the laser scans the multi-layer tab 100 and the workpiece in a continuous line rather than a single point. The weld mark 300 formed by continuously scanning the multi-layer tab 100 and the workpiece is macroscopically strip-shaped or block-shaped.

[0054] S2: Repeat step S1 to form a plurality of discontinuous weld marks 300 at the connection between the multi-layer tab 100 and the workpiece to be welded.

[0055] Generally, a plurality of weld marks 300 spaced apart from each other are formed in the length direction of the multi-layer tab 100 , that is, in the left-right direction in FIG. 2 .

[0056] The battery multi-layer tab welding method provided in the embodiment of the present application forms strip-shaped or block-shaped weld marks 300 on the multi-layer tab 100 and the part to be welded by laser continuous scanning welding. Compared with ultrasonic laser welding, it does not generate mechanical vibration and tear the tab. At the same time, laser continuous scanning welding can increase the weld mark area, and the welding tension and residual area are large, thereby increasing the current flow area of ​​the battery, which is beneficial to the development of battery fast charging technology. In addition, laser welding is a non-contact processing and will not cause wear like the welding seat and welding head of ultrasonic welding (the welding seat and welding head of ultrasonic welding are high-value, fragile and consumable items that need to be replaced and maintained after reaching the number of uses). It does not require frequent replacement and equipment maintenance, thereby reducing maintenance costs. Similarly, compared with quasi-continuous laser welding, the laser scanning trajectory is linear instead of dot-shaped, which increases the weld mark area, and the welding tension and residual area are large, thereby increasing the current flow area of ​​the battery, which is beneficial to the development of battery fast charging technology.

[0057] In some embodiments, a laser welding system is used to continuously scan and weld the multi-layer tab 100 and the workpiece to be welded to form a strip or block weld mark 300. The laser welding system includes a laser generator and a galvanometer. The galvanometer can deflect the laser light emitted by the laser generator onto the multi-layer tab and the workpiece to be welded. The galvanometer can move at a preset angle so that the laser scanning trajectory is a continuous line pattern.

[0058] The above arrangement, through the cooperation of the laser generator and the galvanometer, can make the scanning trajectory of the laser a continuous line pattern.

[0059] The laser generator is a single-mode continuous laser, a type of fiber laser. This type of laser is maintenance-free and can be used continuously for nearly 100,000 hours, significantly reducing maintenance costs. Specifically, the peak power of the laser generator used is less than 2 kW. When the laser is back-reflected, only a small amount of laser energy returns to the laser, making it less likely to burn out. Compared to quasi-continuous lasers with peak powers exceeding 4 kW, single-mode continuous lasers are less susceptible to damage due to back-reflection, have a lower failure rate, extend service life, and further reduce maintenance costs.

[0060] The welding method uses a single-mode continuous laser and a galvanometer. The galvanometer deflects the laser according to the graphics set by the software. The galvanometer has a large scanning range (180mm*180mm), which is much larger than the welding head size of ultrasonic welding (50mm*6mm). It far exceeds the welding size of ultrasonic welding and can accommodate a larger welding area. Ultrasonic welding often requires two or more welding times. The welding method of single-mode continuous laser and galvanometer can complete large-scale welding in one go, thereby improving welding efficiency. At the same time, compared with quasi-continuous laser welding, single-mode continuous laser welding uses linear instead of point-shaped welding, which increases the welding area, has large welding tension and residual area, and thus increases the current flow area of ​​the battery, taking advantage of the development of battery fast charging.

[0061] In one embodiment, referring to FIG3 , the scanning track of single-mode continuous laser welding is changed from a 90-point matrix with a diameter of 1 mm to a rectangular filling of 1 mm*90 mm, and the area is changed from 70.65 mm 2 Became 90mm 2 , the welding area increased by 27%, improving the flow area.

[0062] A single-mode continuous laser replaces a quasi-continuous laser. Single-mode continuous lasers have no duty cycle restrictions (the ratio of laser emission time to emission period), meaning they can emit laser light continuously. During welding, however, a quasi-continuous laser has a duty cycle upper limit of 50%. Single-mode continuous lasers can emit laser light continuously, without duty cycle restrictions. In a preferred embodiment, a quasi-continuous laser welds a 90-dot matrix with a 1mm diameter in 5.9 seconds, while a single-mode continuous laser welds a 1mm*90mm rectangular fill in just 1.9 seconds, a 300% efficiency improvement.

[0063] In some embodiments, a laser is used to continuously scan and weld the multi-layer tab 100 and the workpiece to be welded within a dust removal system, forming a weld mark 300. Referring to FIG4 , the dust removal system includes a first dust removal hood 400 and a second dust removal hood 500. A storage space 800 for accommodating the workpiece to be welded is formed between the first dust removal hood 400 and the second dust removal hood 500. Specifically, the first dust removal hood 400 and the second dust removal hood 500 are arranged vertically. One side of the first dust removal hood 400 and the second dust removal hood 500 can be connected to a compressed air system, and the other side of the first dust removal hood 400 and the second dust removal hood 500 can be connected to an exhaust dust removal device. The compressed air system can blow air into the storage space 800, and the exhaust dust removal device can extract air from the storage space 800 to remove dust. Thus, during laser welding, the workpiece to be welded is placed in the storage space 800, the compressed air system blows compressed air into the storage space 800, and the exhaust dust removal device can suck air from the storage space 800 to remove dust. Specifically, the first dust hood 400 and the second dust hood 500 are both connected to the exhaust dust removal machine through the exhaust dust removal port 600, and the first dust hood 400 and the second dust hood 500 are both connected to the compressed air system through an interface provided with a throttle valve 700.

[0064] It should be noted that, except for the unsealed area where the laser passes, the space enclosed by the first dust cover 400 and the second dust cover 500 is sealed to ensure the centralized discharge of welding slag. Generally, the wind speed in the holding space 800 can reach 25M / s, which can effectively collect flying welding slag.

[0065] In some embodiments, before step S1, the method further includes the following steps:

[0066] The multi-layer tab 100 is pre-welded.

[0067] Pre-welding can initially fix the tabs and prevent them from falling apart. In some embodiments, the multi-layer tabs 100 are pre-welded using an ultrasonic welder. It is contemplated that in other embodiments, the pre-welding method for the multi-layer tabs 100 is not limited.

[0068] In some embodiments, step S1 includes:

[0069] The weld mark 300 is formed by reciprocating scanning or spiral continuous scanning of the laser.

[0070] In some embodiments, the laser scanning trajectory is spiral (see FIG5 ). In some embodiments, the laser scanning trajectory is sequentially scanned from the inside to the outside to form a spiral scanning trajectory. In other embodiments, the laser scanning trajectory is sequentially scanned from the outside to the inside to form a spiral scanning trajectory.

[0071] It should be noted that the above-mentioned spiral shape can be a clockwise spiral or a counterclockwise spiral, and is not limited here.

[0072] In other embodiments, the laser scans continuously and reciprocally along a square waveform, i.e., the laser scanning trajectory is a square wave (see FIG6 ). Specifically, a scanning starting point is selected, and the laser first scans along the longitudinal direction of the multilayer tab 100 for a first length, then bends, scans along the width direction for a second length, then bends again, scans along the longitudinal direction for a first length, then bends, and scans along the width direction for a second length, and repeats this cycle, ultimately forming a square wave scanning trajectory.

[0073] It is conceivable that in some other embodiments, there is no limitation on the scanning trajectory of the laser scanning. For example, the scanning trajectory of the laser can also be a sine waveform or a cosine waveform. Generally, a scanning trajectory with a larger welding area is preferred.

[0074] Furthermore, the plurality of weld marks 300 are arranged at equal intervals along the length direction of the multi-layer tab 100. Of course, in other embodiments, the plurality of weld marks 300 may also be arranged at non-equal intervals along the length direction of the multi-layer tab 100, which is not limited here.

[0075] In some embodiments, a battery multi-layer tab welding method includes:

[0076] Welding positions 1 to N are preset in sequence at the connection between the multi-layer tab 100 and the workpiece to be welded;

[0077] The two weld marks 300 formed at adjacent weld positions are defined as a first weld mark and a second weld mark. A preset time interval exists between the time period during which the first weld mark is welded and the time period during which the second weld mark is welded. The preset time interval is greater than or equal to the minimum time interval between the first and second weld marks at which no heat accumulation effect occurs. The minimum time interval and the preset time interval vary depending on the operating conditions. Specifically, the minimum time interval is related to the size of the weld marks 300 and the distance between the weld marks 300. Accordingly, the preset time interval is also related to the size of the weld marks 300 and the distance between the weld marks 300. Those skilled in the art can determine this based on limited experimentation. In one specific embodiment, the weld mark 300 has a length of 6 mm and a width of 1.5 mm. The spacing between two adjacent weld marks 300 is 2 mm. The welding time for each weld mark 300 is approximately 0.18 seconds. After the welding of the previous weld mark 300 is completed, the welding of the next weld mark 300 is performed after a 0.02 second pause. Furthermore, two weld marks 300 that are adjacent in position (space) are not necessarily adjacent in the welding time period. In other words, two weld marks 300 that are adjacent in position are welded in two non-adjacent time periods. Therefore, the preset time interval is greater than 2 seconds.

[0078] The above arrangement can ensure that each weld mark 300 has sufficient heat dissipation time, facilitate heat dissipation during the welding process, and avoid heat accumulation effects.

[0079] Furthermore, the battery multi-layer tab welding method further includes:

[0080] Welding is performed at odd-numbered welding positions to form weld marks 300;

[0081] Welding marks 300 are formed at even-numbered welding positions.

[0082] In one embodiment, 10 welding positions are preset at the connection between the multi-layer tab 100 and the workpiece to be welded. First, welding is performed at welding positions 1, 3, 5, 7, and 9 to form weld marks 300, and then welding is performed at welding positions 2, 4, 6, 8, and 10 to form weld marks 300.

[0083] In another specific embodiment, the battery multi-layer tab welding method further includes:

[0084] Welding is performed at even-numbered welding positions to form weld marks 300;

[0085] Welding marks 300 are formed at odd-numbered welding positions.

[0086] For example, when 10 welding positions are preset at the connection between the multi-layer tab 100 and the workpiece to be welded, welding can be performed first at welding positions 2, 4, 6, 8, and 10 to form weld marks 300, and then at welding positions 1, 3, 5, 7, and 9 to form weld marks 300.

[0087] In other embodiments, when 10 welding positions are preset at the connection between the multi-layer tab 100 and the workpiece to be welded, other welding methods can also be used. For example, welding can be performed first at welding positions 1, 4, 7, and 10 to form a weld mark 300, then welding can be performed at welding positions 2, 5, and 8 to form a weld mark 300, and finally welding can be performed at welding positions 3, 6, and 9 to form a weld mark 300. Alternatively, welding can be performed first at welding positions 1, 3, 7, and 9 to form a weld mark 300, then welding can be performed at welding positions 2, 4, 6, 8, and 10 to form a weld mark 300, and finally welding can be performed at welding position 5 to form a weld mark 300.

[0088] The above-mentioned welding method, on the one hand, can ensure that there is a preset time interval between the time period in which the first weld mark is welded and the time period in which the second weld mark is welded. On the other hand, compared with the situation in which the adjacent first weld mark and the second weld mark are welded in two adjacent time periods, it can reduce the intermediate waiting time and improve the welding efficiency.

[0089] Of course, in other embodiments, adjacent first weld marks and first weld marks at the welding positions of two adjacent segments may also be welded, which is not limited here.

[0090] Another embodiment of the present application provides a battery manufactured using the above-described multi-layer tab welding method. The battery includes a multi-layer tab 100 and an electrical adapter 200, wherein the electrical adapter 200 is laser-welded to the multi-layer tab 100. The connection between the electrical adapter 200 and the multi-layer tab 100 has multiple discontinuous strip-shaped or block-shaped weld marks 300. Each weld mark 300 is formed by reciprocating or spiral continuous laser scanning.

[0091] It should be noted that the electrical adapter 200 is a TAB sheet, which can conduct current and output voltage and current. It can be used as the positive and negative poles of the battery cell to connect with other battery cells or electrical appliances.

[0092] In the battery provided in the embodiment of the present application, the weld mark 300 is formed by reciprocating continuous scanning or spiral continuous scanning of the laser. The scanning trajectory of the laser is linear instead of dot-shaped, which increases the weld mark area, increases the welding tension and residual area, and thereby increases the current flow area of ​​the battery, taking advantage of the development of battery fast charging.

[0093] Furthermore, the plurality of weld marks 300 are arranged at equal intervals along the length direction of the multi-layer tab 100 to ensure uniformity of the weld marks 300. Of course, in other embodiments, the plurality of weld marks 300 may also be arranged at unequal intervals along the length direction of the multi-layer tab 100, which is not limited here.

[0094] The battery multi-layer tab welding method provided in the embodiment of the present application has the following beneficial effects:

[0095] 1. The battery multi-layer tab welding method uses a single-mode continuous laser and galvanometer welding, which significantly increases the speed compared to ultrasonic welding and quasi-continuous laser pulse spot welding (peak 4500W), thereby improving the welding efficiency.

[0096] 2. Compared with quasi-continuous laser pulse spot welding, the efficiency of single-mode continuous laser is small, and the equipment cost is reduced by more than 70%. Compared with ultrasonic welding (ultrasonic welding seat and welding head are consumables), single-mode continuous laser is maintenance-free equipment, and the maintenance cost is much lower than that of ultrasonic welding machine.

[0097] 3. Compared with quasi-continuous laser welding, the laser scanning trajectory is linear instead of point-shaped, which increases the weld area, the welding tension and residual area are large, thereby increasing the current flow area of ​​the battery and utilizing the development of battery fast charging.

[0098] 4. The dust removal system can effectively collect welding slag and prevent welding slag from splashing during welding.

[0099] The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0100] The above-described embodiments merely represent several implementation methods of the present disclosure. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that a person of ordinary skill in the art could make various modifications and improvements without departing from the spirit of the present disclosure, all of which fall within the scope of protection of the present disclosure. Therefore, the scope of protection of the present patent shall be determined by the appended claims.

Claims

1. A method for welding multi-layer tabs of a battery, comprising the steps of: S1: using laser to continuously scan and weld the multilayer tab (100) and the workpiece to be welded to form a strip or block weld mark (300); S2: Repeat step S1 to form a plurality of discontinuous weld marks (300) at the connection between the multilayer tab (100) and the part to be welded.

2. The battery multi-layer tab welding method according to claim 1, wherein: The step S1 comprises: The welding mark (300) is formed by reciprocating continuous scanning or spiral continuous scanning of the laser.

3. The battery multi-layer tab welding method according to claim 2, wherein: The laser reciprocating continuous scanning is: The laser scans reciprocatingly and continuously along at least one of a square waveform, a sine waveform and a cosine waveform.

4. The battery multi-layer tab welding method according to any one of claims 1 to 3, wherein: Welding positions 1 to N are sequentially preset at the connection between the multilayer tab (100) and the part to be welded; The two weld marks (300) formed at adjacent welding positions are defined as a first weld mark and a second weld mark, and a preset time interval exists between a time period for welding the first weld mark and a time period for welding the second weld mark, and the preset time interval is greater than or equal to a minimum time interval between the first weld mark and the second weld mark in which there is no heat accumulation effect.

5. The battery multi-layer tab welding method according to any one of claims 1 to 4, wherein: include: Welding positions 1 to N are preset at the connection between the multilayer tab (100) and the part to be welded; Welding at the odd-numbered welding positions to form the welding marks; Welding at the even-numbered welding positions to form the weld marks; or Welding positions 1 to N are preset at the connection between the multilayer tab (100) and the part to be welded; Welding at the even-numbered welding positions to form the welding marks; The welding marks are formed by welding at the odd-numbered welding positions.

6. The battery multi-layer tab welding method according to any one of claims 1 to 5, wherein: The parts to be welded are electrical adapters.

7. The battery multi-layer tab welding method according to any one of claims 1 to 6, wherein: include: Using a laser welding system to continuously scan and weld the multilayer tab (100) and the workpiece to be welded to form the weld mark (300); The laser welding system comprises a laser generator and a galvanometer, wherein the galvanometer can deflect the laser emitted by the laser generator to the multilayer tab (100) and the workpiece to be welded, and the galvanometer can move at a preset angle so that the scanning trajectory of the laser is a continuous line pattern.

8. The battery multi-layer tab welding method according to any one of claims 1 to 7, wherein: The laser is a single-mode continuous laser.

9. The battery multi-layer tab welding method according to any one of claims 1 to 8, wherein: Using laser to continuously scan and weld the multi-layered pole tab (100) and the workpiece to be welded in the dust removal system to form the weld mark (300); The dust removal system comprises a first dust removal hood (400) and a second dust removal hood (500), wherein a storage space (800) for storing the parts to be welded is formed between the first dust removal hood (400) and the second dust removal hood (500); one side of the first dust removal hood (400) and the second dust removal hood (500) can be connected to a compressed air system, and one side of the first dust removal hood (400) and the second dust removal hood (500) can be connected to an exhaust dust removal machine; the compressed air system can blow air into the storage space (800), and the exhaust dust removal machine can extract gas from the storage space (800) to remove dust.

10. A battery comprising: Multilayer tabs (100); An electrical adapter (200) is laser welded to the multi-layered tab (100); a connection between the electrical adapter (200) and the multi-layered tab (100) has a plurality of discontinuous strip-shaped or block-shaped weld marks (300); Wherein, each of the weld marks (300) is formed by reciprocating continuous scanning or spiral continuous scanning of the laser.

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