Welding method for multiple layers of tabs and battery assembly

Abstract

The invention discloses a welding method of a multi-layer tab and a battery assembly, the welding method is used for welding the multi-layer tab on a switching piece, the multi-layer tab comprises a first edge connected with a battery cell and a second edge arranged opposite to the first edge, and the welding method comprises the following steps: placing at least part of the multi-layer tab on the switching piece; wherein the second edge is located on the adapter piece; laser is used for melting the second edge, so that the multiple layers of tabs and the switching piece are welded and fixed, and a welding printing area with a lap joint is formed; wherein one part of the lap joint is located on the multiple layers of tabs, and the other part of the lap joint is located on the adapter plate. According to the welding method provided by the invention, the loose multiple layers of tabs are directly welded together with the adapter plate by directly penetrating the multiple layers of tabs through laser, ultrasonic pre-welding and tab cutting and shaping are not needed, and the technical problem of short circuit risk caused by foreign matters such as chippings and burrs entering a pole core in the welding process of a traditional welding method is solved; and the processing yield and the product safety performance are obviously improved.

Description

Technical Field

[0001] The invention belongs to the technical field of battery manufacturing and relates to a multi-layer pole ear welding method and a battery assembly. Background Art

[0002] In the production and manufacturing process of batteries, the welding of multi-layer pole ears and cover plates is an important process in the battery production process and plays an important connecting role. In the traditional welding process, when welding multi-layer pole ears and cover plates, the multi-layer pole ears are first pre-welded by ultrasonic welding, and then the excess tower-shaped pole ears are cut and shaped, and finally the cut multi-layer pole ears and cover plates are welded together. This method has complicated manufacturing processes, and the ultrasonic pre-welding and subsequent pole ear cutting and shaping processes are prone to produce foreign matter such as debris and burrs, which increases the risk of foreign matter entering the pole core and causing a short circuit. In addition, ultrasonic welding machines are expensive, which increases manufacturing costs. Summary of the invention

[0003] In view of this, the present invention provides a multi-layer pole ear welding method and a battery assembly, which solves the technical problem of foreign matter such as debris and burrs entering the pole core during the welding process and causing the risk of short circuit in traditional welding methods.

[0004] In order to solve the above problems, according to one aspect of the present application, an embodiment of the present invention provides a welding method of a multi-layer tab, which is used to weld the multi-layer tab to a transfer sheet, wherein the multi-layer tab includes a first side connected to the battery cell and a second side arranged opposite to the first side, and the welding method of the multi-layer tab includes:

[0005] S1, placing at least a portion of the multi-layer tab on the adapter; wherein the second edge is located on the adapter;

[0006] S2, using laser to melt the second edge, so that the multi-layer pole ear and the adapter are welded and fixed, and a weld print area with a lap joint is formed; wherein a part of the lap joint is located on the multi-layer pole ear, and the rest is located on the adapter.

[0007] In some embodiments, the step of melting the second edge using a laser in S2 includes:

[0008] The light outputted by the laser optical fiber is converted from divergent light to parallel light; the parallel light is offset; the offset parallel light is focused and then welded, so that the laser focus point moves on the multi-layer pole ear as required.

[0009] In some embodiments, moving the laser focus on the multi-layer tab as required comprises:

[0010] Through a single-mode laser, galvanometer scanning filling is adopted. According to a pre-set welding pattern, scanning welding is performed by controlling the galvanometer motor along a preset trajectory. The focused light beam scans back and forth between the edge of the multi-layer pole ear and the position of the adapter, and small holes are formed on the surface of the multi-layer pole ear and the adapter.

[0011] In some embodiments, the welding pattern filled by the galvanometer scanning includes a rectangular outline, and the outline has a plurality of filling lines with fixed spacing, and the filling lines are oblique lines or straight lines;

[0012] And / or the width of the contour is 3-8 mm, the length of the contour is 5-50 mm, the spacing of the filling lines is 0.05-0.5 mm, the scanning speed of the galvanometer is 200-500 mm / s, the welding power of the laser is 500-4000 W, and the defocus amount is ±3 mm.

[0013] In some embodiments, placing at least a portion of the multilayer tab on the adapter sheet in S1 is specifically:

[0014] First, the adapter is placed on the lower pressing plate, then at least a portion of the multi-layer tab is placed on the adapter, and finally an upper pressing plate is placed on the multi-layer tab to compress the periphery of the second side.

[0015] In some embodiments, the step S2 uses a laser to melt the second edge, specifically:

[0016] The laser is welded through the laser through hole on the upper pressing plate, and a protective gas is introduced into the upper pressing plate at the same time; wherein the flow direction of the protective gas is opposite to the welding direction.

[0017] In some embodiments, the flow rate of the protective gas is between 10-50 L / min;

[0018] And / or the protective gas is nitrogen or argon.

[0019] In some embodiments, the distance between the side of the weld stamping area close to the upper pressing plate and the upper pressing plate is 0.5 mm-3 mm;

[0020] And / or the distance between the side of the weld print area close to the lower pressing plate and the lower pressing plate is 0.5 mm-3 mm.

[0021] In some embodiments, the length of the weld print area is 5-50 mm and the width is 3-8 mm; and an arc-shaped molten pool is formed on the width side of the weld print area.

[0022] According to another aspect of the present application, an embodiment of the present invention provides a battery assembly, which includes a battery tab and a cover plate, wherein the battery tab is connected to the cover plate through the adapter plate, and the battery tab is welded to the adapter plate by the above-mentioned welding method.

[0023] Compared with the prior art, the welding method of the multilayer tab of the present invention has at least the following beneficial effects:

[0024] The welding method of the multi-layer pole ear provided by the present invention is used for welding the multi-layer pole ear to an adapter sheet, the multi-layer pole ear includes a first side connected to the battery cell and a second side arranged opposite to the first side, and the welding method of the multi-layer pole ear includes: placing at least a portion of the multi-layer pole ear on the adapter sheet; wherein the second side is located on the adapter sheet; using a laser to melt the second side so that the multi-layer pole ear and the adapter sheet are welded and fixed, and a weld print area with a lap joint is formed; wherein a portion of the lap joint is located on the multi-layer pole ear, and the remaining portion is located on the adapter sheet.

[0025] The welding method of the multi-layer pole ear provided by the present invention is different from the conventional welding of the multi-layer pole ear and the adapter sheet. During welding, the welding position is in the ultrasonic welding area inside the pole ear. After welding, all the molten pools are located on the multi-layer pole ear, and do not directly act on the adapter sheet. Instead, the multi-layer pole ear is penetrated by stack welding to fuse with the adapter sheet. The present invention directly penetrates the multi-layer pole ear by laser, and directly welds the loose multi-layer pole ear to the adapter sheet, without the need for ultrasonic pre-welding and pole ear cutting and shaping, which solves the technical problem of foreign matter such as debris and burrs entering the pole core during the welding process to generate a short circuit risk in the traditional welding method, and significantly improves the processing yield and product safety performance.

[0026] The battery assembly provided by the present invention is designed based on the above-mentioned multi-layer electrode tab welding method. Its beneficial effects refer to the beneficial effects of the above-mentioned multi-layer electrode tab welding method, which will not be described in detail here.

[0027] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention and implement it according to the contents of the specification, the following is a detailed description of the preferred embodiments of the present invention in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying any creative work.

[0029] Figure 1It is a diagram of the coordination of a battery cell, a multi-layer tab and a transfer plate in a multi-layer tab welding method provided by an embodiment of the present invention;

[0030] Figure 2 It is a schematic diagram of a lap joint formed by welding a multi-layer electrode tab and a transfer plate in a multi-layer electrode tab welding method provided by an embodiment of the present invention;

[0031] Figure 3 It is a structural schematic diagram of a multi-layer tab welding method provided by an embodiment of the present invention, when the multi-layer tab is in a cut state, the multi-layer tab cooperates with a transfer sheet;

[0032] Figure 4 yes Figure 3 An enlarged view of the mating point between the middle multi-layer tab and the adapter;

[0033] Figure 5 It is a structural schematic diagram of a multi-layer tab welding method provided by an embodiment of the present invention, when the multi-layer tab is in a staggered state, the multi-layer tab cooperates with a transfer sheet;

[0034] Figure 6 yes Figure 5 An enlarged view of the mating point between the middle multi-layer tab and the adapter;

[0035] Figure 7 It is a flow chart of a multi-layer tab welding method provided by an embodiment of the present invention.

[0036] in:

[0037] 1. Multi-layer tabs; 11. First side; 12. Second side; 2. Adapter; 3. Lap joint; 4. Battery cell; 5. Laser beam; 6. Welding area. DETAILED DESCRIPTION

[0038] In order to further explain the technical means and effects adopted by the present invention to achieve the predetermined invention purpose, the specific implementation methods, structures, features and effects of the present invention application are described in detail below in conjunction with the accompanying drawings and preferred embodiments. In the following description, different "one embodiment" or "embodiment" does not necessarily refer to the same embodiment. In addition, specific features, structures, or characteristics in one or more embodiments may be combined in any suitable form.

[0039] In the description of the present invention, it should be clarified that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, but are not necessarily used to describe a specific order or sequence; the terms "vertical", "lateral", "longitudinal", "front", "rear", "left", "right", "up", "down", "horizontal", etc. indicating directions or positional relationships are based on the directions or positional relationships shown in the drawings, and are only for the convenience of describing the present invention, and do not mean that the referred device or element must have a specific direction or position, and therefore cannot be understood as a limitation on the present invention.

[0040] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" 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. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0041] Example 1

[0042] This embodiment provides a multi-layer tab welding method, such as Figure 1-6 As shown, a multilayer tab 1 is welded on a transfer sheet 2, wherein the multilayer tab 1 comprises a first side 11 connected to a battery cell 4 and a second side 12 arranged opposite to the first side 11. The welding method of the multilayer tab comprises:

[0043] S1, placing at least a portion of the multi-layer tab 1 on the adapter sheet 2; wherein the second edge 12 is located on the adapter sheet 2;

[0044] S2, using laser to melt the second edge 12, so that the multi-layer pole ear 1 and the adapter plate 2 are welded and fixed, and a weld print area 6 with a lap joint 3 is formed; wherein a portion of the lap joint 3 is located on the multi-layer pole ear 1, and the remaining portion is located on the adapter plate 2.

[0045] Specifically, the adapter 2 is a structure on the battery cover, and the battery cover includes components such as poles, retaining frames, adapters 2, and sealing rings. Generally, the positive poles and negative poles are directly connected to the adapter 2, and the connection between the multi-layer pole tabs 1 and the cover is achieved by laser direct welding of the multi-layer pole tabs 1 and the adapter 2. The aluminum pole tabs need to be welded on the aluminum adapter, and the copper pole tabs are welded on the copper adapter. The adapter 2 has a length of 5-100 mm, a width of 5-60 mm, and a thickness of 0.5-2 mm.

[0046] In this embodiment, the multi-layer tab 1 adopts different materials and thicknesses according to the positive and negative electrodes of the connected battery. Among them, the tab connected to the positive electrode cover of the battery is an aluminum tab with 50-120 layers, and the thickness of a single-layer aluminum tab is 0.01-0.02mm; the tab connected to the negative electrode cover of the battery is a copper tab with 50-120 layers, and the thickness of a single-layer copper tab is 0.004-0.01mm.

[0047] The multilayer tab 1 in step 1 of this embodiment refers to a neatly stacked multilayer tab. The lap joint 3 refers to the multilayer tab 1 being on the adapter 2 before welding, the welding position being located at the junction of the edge of the multilayer tab 1 and the adapter 2 during welding, and a part of the molten pool being located at the edge of the multilayer tab 1 and the other part being located on the adapter 2 after welding. This welding method is called lap joint, and a lap joint structure 3 will be formed after lap welding.

[0048] The welding method of the multi-layer pole ear provided in this embodiment is different from the conventional welding of the multi-layer pole ear and the adapter plate. During welding, the welding position is in the ultrasonic welding area inside the pole ear. After welding, all the molten pools are located on the multi-layer pole ear. They do not act directly on the adapter plate, but penetrate the multi-layer pole ear 1 and fuse with the adapter plate 2 by means of overlap welding.

[0049] The multi-layer pole ear welding method provided in the present embodiment directly penetrates the multi-layer pole ear through the laser, and directly welds the loose multi-layer pole ear 1 and the adapter plate 2 together, without the need for ultrasonic pre-welding and pole ear cutting and shaping. This solves the technical problem of foreign matter such as debris and burrs entering the pole core during the welding process and causing the risk of short circuit in the traditional welding method, and significantly improves the processing yield and product safety performance.

[0050] In a specific embodiment, the second edge 12 is melted by laser in S2, such as Figure 7 As shown, it includes: converting the light output by the laser optical fiber from divergent light into parallel light; offsetting the parallel light; focusing the offset parallel light and then welding it, so that the laser focus point moves on the multi-layer pole ear 1 according to the required requirements.

[0051] Specifically, in one embodiment, a galvanometer system is used to collimate and focus the laser beam 5 for welding, and the galvanometer system includes a laser collimation module, a scanning galvanometer module and a laser focusing module. The collimation module is a device that converts the light output by the laser optical fiber from divergence to parallel light; the scanning galvanometer deflects the light beam by controlling the high-precision motor in the internal X / Y direction; the focusing module finally focuses the deflected parallel light, so that the laser focus point with a certain power density moves on the material according to the required requirements.

[0052] In a specific embodiment, the laser focal point is moved on the multi-layer pole ear 1 according to the required requirements, including: using a single-mode laser, adopting a galvanometer scanning and filling, and scanning and welding according to a preset welding pattern by controlling the galvanometer motor along a preset trajectory, and the focused light beam scans back and forth between the edge of the multi-layer pole ear 1 and the position of the adapter plate 2, and small holes are formed on the surfaces of the multi-layer pole ear 1 and the adapter plate 2.

[0053] Specifically, the laser uses a single-mode laser, the core diameter of the central fiber of the laser mode is 20um, and the core diameter of the ring fiber is 200μm. The welding method uses galvanometer scanning and filling. The graphics to be welded are pre-set in CAD or welding software. The galvanometer XY motor is controlled to scan and weld according to the preset trajectory. The focused beam will quickly scan back and forth at the edge of the pole ear and the adapter position, and quickly form small holes on the surface of the material.

[0054] This small hole fast moving welding method can produce a stable molten pool and realize the welding of the foil and the cover plate lead-out sheet. Because of the scanning filling method, the laser is prevented from staying at the edge of the foil for a long time, thereby avoiding the undesirable phenomenon that the foil is deformed due to long-term heat input and cannot form a stable molten pool. Compared with the traditional method of one heat conduction welding and two deep fusion welding, the method provided in this embodiment can realize the welding of the foil and the cover plate in one welding, which is more efficient.

[0055] In a specific embodiment, the welding pattern filled by the galvanometer scanning includes a rectangular outline, and the outline has a plurality of filling lines with fixed intervals, and the filling lines are oblique lines or straight lines.

[0056] In a specific embodiment, the width of the contour is 3-8 mm, the length of the contour is 5-50 mm, the spacing of the filling lines is 0.05-0.5 mm, the scanning speed of the galvanometer is 200-500 mm / s, the welding power of the laser is 500-4000 W, and the defocus amount is ±3 mm.

[0057] In a specific embodiment, the step S1 is to place at least a portion of the multilayer tab 1 on the adapter sheet 2, such as Figure 7 As shown, specifically: first, the adapter plate 2 is placed on the lower pressure plate, then at least a portion of the multi-layer tab 1 is placed on the adapter plate 2, and finally, the upper pressure plate is placed on the multi-layer tab 1 to compress the periphery of the second side.

[0058] Specifically, neatly stacked multi-layer pole lugs 1 and adapter plates 2 are provided, and the adapter plates 2 are first placed on the lower pressure plate, and then the multi-layer pole lugs 1 are placed on the adapter plates 2, and then the upper pressure plate is used to press around the welding position to ensure that there is no gap between the multi-layer pole lugs 1 and the adapter plates 2 of the cover plate.

[0059] In a specific embodiment, laser is used to melt the second side in S2, specifically: laser welding is performed through the laser through-hole on the upper pressing plate, and protective gas is introduced into the upper pressing plate at the same time; wherein the flow direction of the protective gas is opposite to the welding direction.

[0060] During welding, the shielding gas forms a steady flow in the weld mark area 6 and the laser through hole, which can effectively prevent the surface oxidation of the weld joint, inhibit spatter, and stabilize the welding keyhole. The shielding gas is mainly high-purity nitrogen or argon, which can obtain a better welding appearance.

[0061] In addition, during the welding process, the upper pressing plate has a laser through hole. When the upper pressing plate is pressed onto the multi-layer pole ear 1, the welding part of the multi-layer pole ear 1 and the adapter plate 2 can be exposed through the laser through hole, and the laser is emitted toward the laser through hole to form the weld mark area 6.

[0062] In addition, the laser welds the edge of the multi-layer pole ear 1 to the adapter plate 2 from left to right by welding the weld mark area 6, which needs to be opposite to the steady flow direction formed by the protective gas. This can effectively prevent the smoke and impurities generated during welding from contaminating the areas that have not been welded, ensure the cleanliness of the subsequent welding areas, and improve the yield during welding.

[0063] In a specific embodiment, the flow rate of the shielding gas is between 10-50 L / min; if the flow rate is too small, the plasma generated during welding and the smoke and impurities evaporated from the material cannot be taken away, the light is blocked, the welding keyhole loses its stable state, the penetration depth fluctuates greatly, and the smoke and impurities will also adhere to the weld area, affecting the joint performance and weld appearance; if the flow rate is too large, the shielding gas will significantly reduce the temperature during welding, resulting in a longer time to form the molten pool keyhole, and the impact force of the shielding gas on the molten pool during welding will affect the steady state of the molten pool keyhole.

[0064] In a specific embodiment, the protective gas is nitrogen or argon. The protective gas is generally based on high-purity nitrogen or high-purity argon. In some special cases, nitrogen and compressed air are mixed in different proportions.

[0065] In a specific embodiment, the distance between the side of the weld mark area 6 close to the upper pressing plate and the upper pressing plate is 0.5mm-3mm; and / or the distance between the side of the weld mark area 6 close to the lower pressing plate and the lower pressing plate is 0.5mm-3mm.

[0066] A certain distance must be maintained between the weld area 6 and the upper platen, and between the weld area 6 and the lower platen, and the distance S is 0.5mm-3mm; in principle, the closer the distance, the better the pressing effect, but it is easy to block the laser beam 5, and if the distance is too far, the multi-layer tab 1 is in a steady flow of protective gas during welding, and the impact force of the laser beam 5 during welding will cause gaps or deformation in the multi-layer tab 1, affecting the welding effect. After multiple verifications, the distance between 0.5mm-3mm has the best pressing effect and does not affect the welding effect.

[0067] In a specific embodiment, the length L of the weld area 6 is 5-50 mm, and the width W is 3-8 mm; wherein the length direction is set according to the width of the tab, and a press-fitting position needs to be reserved. The width dimension is set according to the tower-shaped area after the tabs are gathered.

[0068] And an arc-shaped molten pool is formed on the width side of the weld mark area 6. Compared with penetration welding, the surface tension of the welding molten pool makes it easier to obtain a stable molten pool, thereby overcoming the gap between the foils and achieving welding.

[0069] In the production and manufacturing process of square shell batteries, laser penetration welding is currently used for welding the pole ears and the cover plate. Due to the gaps between the foils, it is necessary to first perform ultrasonic pre-welding on the multi-layer pole ears, weld the loose pole ears together, and then use a laser to weld the pre-welded pole ears to the cover plate. At the same time, due to the existence of ultrasonic pre-welding, it is necessary to cut off the excess tower-shaped pole ears after ultrasonic pre-welding, so it is necessary to add a cutting and shaping process. This method has complicated procedures and a high defect rate; and foreign matter such as debris and burrs generated by pre-welding and cutting increase the risk of battery short circuit. The multi-layer pole ear welding method provided in this embodiment adopts a lap welding method, which can realize direct welding of the foil and the cover plate, eliminate the step of ultrasonic pre-welding of the multi-layer pole ears, and there is no need to consider the subsequent process of cutting the pole ears, which greatly reduces the battery processing steps, increases the battery capacity, improves the production efficiency, and reduces the production cost.

[0070] Example 2

[0071] This embodiment provides a battery assembly, which includes a battery tab 1 and a cover plate, wherein the battery tab 1 is connected to the cover plate via the adapter plate 2, and the battery tab 1 is welded to the adapter plate 2 by the welding method described in Example 1.

[0072] In summary, it is easy for those skilled in the art to understand that, under the premise of no conflict, the above-mentioned advantageous technical features can be freely combined and superimposed.

[0073] The above are only preferred embodiments of the present invention and are not intended to limit the present invention in any form. Any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A method for welding a multi-layer tab, for welding the multi-layer tab to a transfer sheet, wherein the multi-layer tab comprises a first side connected to a battery cell and a second side arranged opposite to the first side, characterized in that: The welding method of the multi-layer tab comprises: S1, placing at least a portion of the multi-layer tab on the adapter; wherein the second edge is located on the adapter; S2, using laser to melt the second edge, so that the multi-layer pole ear and the adapter are welded and fixed, and a weld print area with a lap joint is formed; wherein a part of the lap joint is located on the multi-layer pole ear, and the rest is located on the adapter.

2. The multi-layer tab welding method according to claim 1, characterized in that: The step S2 uses a laser to melt the second edge, including: converting the light output by the laser optical fiber from divergent light into parallel light; offsetting the parallel light; focusing the offset parallel light and then welding it, so that the laser focus point moves on the multi-layer pole ear as required.

3. The welding method of multi-layer tabs according to claim 2, characterized in that: The laser focus point is moved on the multi-layered tab as required, comprising: Through a single-mode laser, galvanometer scanning filling is adopted. According to a pre-set welding pattern, scanning welding is performed by controlling the galvanometer motor along a preset trajectory. The focused light beam scans back and forth between the edge of the multi-layer pole ear and the position of the adapter, and small holes are formed on the surface of the multi-layer pole ear and the adapter.

4. The welding method of multi-layer tabs according to claim 3, characterized in that: The welding pattern filled by the galvanometer scanning includes a rectangular outline, and the outline has a plurality of filling lines with fixed spacing, and the filling lines are oblique lines or straight lines; And / or the width of the contour is 3-8mm, the length of the contour is 5-50mm, the spacing of the filling lines is 0.05-0.5mm, the scanning speed of the galvanometer is 200-500mm / s, the welding power of the laser is 500-4000W, and the defocus of the laser is ±3mm.

5. The welding method of multi-layer tabs according to claim 1, characterized in that: Placing at least a portion of the multilayer tab on the adapter sheet in S1 is specifically: First, the adapter is placed on the lower pressing plate, then at least a portion of the multi-layer tab is placed on the adapter, and finally an upper pressing plate is placed on the multi-layer tab to compress the periphery of the second side.

6. The welding method of multi-layer tabs according to claim 5, characterized in that: In S2, the second side is melted by laser, specifically: The laser is welded through the laser through hole on the upper pressing plate, and a protective gas is introduced into the upper pressing plate at the same time; wherein the flow direction of the protective gas is opposite to the welding direction.

7. The welding method of multi-layer tabs according to claim 6, characterized in that: The flow rate of the protective gas is between 10-50L / min; And / or the protective gas is nitrogen or argon.

8. The welding method of multi-layer tabs according to claim 5, characterized in that: The distance between the side of the welding area close to the upper pressing plate and the upper pressing plate is 0.5mm-3mm; And / or the distance between the side of the weld print area close to the lower pressing plate and the lower pressing plate is 0.5 mm-3 mm.

9. The multi-layer tab welding method according to claim 1, characterized in that: The length of the weld print area is 5-50 mm and the width is 3-8 mm; and an arc-shaped molten pool is formed on the width side of the weld print area.

10. A battery assembly, characterized in that: The battery assembly includes a battery tab and a cover plate, the battery tab is connected to the cover plate via the adapter plate, and the battery tab is welded to the adapter plate by the welding method according to any one of claims 1 to 9.

Images