Welding methods, welded products and battery modules
By overlapping and positioning multiple substrates and welding them in a non-overlapping spiral pattern, a continuous spiral pattern is formed using laser welding technology. This solves the problems of spatter and notch effect in spiral pattern welding, improves mechanical properties and welding quality, and enhances space utilization.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- LG ENERGY SOLUTION LTD
- Filing Date
- 2025-03-06
- Publication Date
- 2026-07-31
AI Technical Summary
Existing technologies for spiral pattern welding suffer from problems such as excessive spatter, severe notch effect, deterioration of mechanical properties, and difficulty in real-time welding quality inspection, especially when welding small diameters or at high speeds.
Multiple substrates are overlapped and positioned and welded in a non-overlapping manner with multiple spiral patterns. A laser device is used to weld with a laser at 1030 nm to 1070 nm to form continuous first and second spiral patterns with non-overlapping and appropriately spaced weld lines.
It reduces spatter and notch effects, improves mechanical properties and the possibility of real-time weld quality inspection, enhances space utilization, and maintains mechanical properties with similar loads while reducing diameter.
Smart Images
Figure CN122497566A_ABST
Abstract
Description
Technical Field
[0001] Cross-reference of related technologies
[0002] This application is based on and claims priority to Korean Patent Application No. 10-2024-0033203 filed with the Korean Intellectual Property Office on March 8, 2024, and Korean Patent Application No. 10-2025-0028016 filed with the Korean Intellectual Property Office on March 5, 2025, the disclosures of which are incorporated herein by reference in their entirety. Technical Field
[0004] This disclosure relates to welding methods, welding products, and battery modules. Background Technology
[0005] The application of multiple conventional spiral pattern weld sections can cause problems, such as excessive spatter at the start / end sections and notch effects due to the weld bead shape at the end of the spiral pattern. Additionally, it can reduce the likelihood of inspection when combined with real-time weld quality checks.
[0006] Furthermore, the continuous melting of welding fixtures due to the large amount of spatter generated has adverse effects on maintenance / repair.
[0007] The notch effect at the ends of the spiral pattern acts as a factor that can degrade mechanical properties under repeated loads.
[0008] If the weld diameter is small or the welding time is shortened due to high welding speed, there is a risk of reducing the possibility of real-time weld quality inspection. Summary of the Invention
[0009] Technical issues
[0010] One aspect of this disclosure is to provide welding methods, welded products, and battery modules that can reduce spatter and improve mechanical properties.
[0011] Technical solution
[0012] The welding method according to embodiments of the present disclosure includes: a positioning process in which multiple substrates are positioned to overlap each other; and a welding process in which multiple substrates are welded together to form a predetermined welding pattern, wherein the welding process welds the welding pattern in the form of multiple spiral patterns connected without overlap.
[0013] Additionally, the welded product according to embodiments of the present disclosure includes: a plurality of substrates positioned to overlap each other; and a predetermined weld pattern formed by welding the plurality of substrates together, wherein the weld pattern forms a plurality of spiral patterns, and the plurality of spiral patterns do not overlap and are connected.
[0014] Furthermore, the battery module according to embodiments of the present disclosure includes a welded product according to embodiments of the present disclosure.
[0015] Beneficial effects
[0016] According to this disclosure, when multiple substrates are welded together to form a weld pattern in the form of multiple connected spiral patterns, continuous welding without overlapping weld lines can reduce spatter, improve mechanical properties, increase space utilization, and enhance the possibility of real-time weld quality inspection.
[0017] Additionally, according to this disclosure, the welding lines of multiple spiral patterns can be welded continuously without overlapping, thereby preventing degradation of the mechanical and material properties of the welded portion due to the high heat generated when the welding lines overlap. Furthermore, the notch effect that occurs when multiple spiral patterns each form a separate pattern can be significantly reduced.
[0018] Furthermore, according to this disclosure, the plurality of spiral patterns include a first spiral pattern and a second spiral pattern, and the welding begins at the center of the first spiral pattern and ends at the center of the second spiral pattern, such that the two spiral patterns can form a non-overlapping continuous pattern, thereby ensuring mechanical properties that can withstand similar loads even if the diameter of the welded portion (welded pattern) is reduced. Attached Figure Description
[0019] Figure 1 This is a plan view showing the welding process in a welding method according to an embodiment of the present disclosure.
[0020] Figure 2 This is a reference numeral showing a weld pattern formed by a welding process according to a welding method according to an embodiment of the present disclosure.
[0021] Figure 3 This is a perspective view showing an example of a welded product welded by a welding method according to an embodiment of the present disclosure.
[0022] Figure 4 This is an exemplary plan view of a welded portion of a welded product welded by a welding method according to an embodiment of the present disclosure.
[0023] Figure 5This is an enlarged plan view showing a welded portion of another example of a welded product welded by a welding method according to an embodiment of the present disclosure.
[0024] Figure 6 This is a cross-sectional view of a secondary battery, which is used in another example of a welded product welded by a welding method according to an embodiment of the present disclosure.
[0025] Figure 7 This is a perspective view showing another example of a welded product welded by a welding method according to an embodiment of the present disclosure.
[0026] Figure 8 This is an external photograph showing the fracture state of a welded product welded according to the welding method of the comparative example.
[0027] Figure 9 This is an external photograph showing the fracture state of a welded product welded according to a welding method based on a manufacturing example.
[0028] Figure 10 It is a graph showing the tensile load of a welded product welded according to the welding method of the comparative example.
[0029] Figure 11 It is a graph showing the tensile load of a welded product welded according to the welding method of the manufacturing example. Detailed Implementation
[0030] The objectives, specific advantages, and novel features of this disclosure will become more apparent from the following detailed description and preferred embodiments in conjunction with the accompanying drawings. It should be noted that, when affixing reference numerals to elements in each of the figures in this specification, identical reference numerals are affixed to the same elements whenever possible, even if these identical elements are shown in different figures. Additionally, this disclosure may be implemented in many different forms and is not limited to the embodiments described herein. Furthermore, in describing this disclosure, detailed descriptions of related known techniques that may unnecessarily obscure the essential points of this disclosure will be omitted.
[0031] Welding method according to the embodiment
[0032] Figure 1 This is a plan view showing the welding process in a welding method according to an embodiment of the present disclosure, and Figure 2 This is a reference numeral showing a weld pattern formed by a welding process according to a welding method according to an embodiment of the present disclosure.
[0033] Reference Figure 1 and Figure 2The welding method according to the embodiments of the present disclosure can manufacture the welded product 100 by including the following processes: a positioning process of positioning a plurality of substrates 130 to overlap each other; and a welding process of welding the plurality of substrates 130 together to form a predetermined welding pattern 160.
[0034] More specifically, the positioning process can position multiple substrates 130 to overlap each other.
[0035] Additionally, the positioning process may position the plurality of substrates 130 such that the width w1 of the overlapping portion of the plurality of substrates 130 is 8 mm to 15 mm. Here, the plurality of substrates 130 may include a first substrate 110 and a second substrate 120, and the width w1 of the overlapping portion of the first substrate 110 and the second substrate 120 may be, for example, 8 mm to 15 mm. Here, the width w1 of the overlapping portion of the plurality of substrates 130 may be, for example, the width w1 in a direction parallel to the width direction W of the welding pattern 160, which is perpendicular to the length (extension) direction G of the welding pattern 160.
[0036] During the welding process, multiple substrates 130 are welded into multiple spiral patterns. At this time, the welding process produces a weld pattern 160 by connecting multiple spiral patterns without overlapping.
[0037] Alternatively, the welding process can be performed using multiple spiral patterns 140, 150 in which two or more spiral patterns are connected.
[0038] Furthermore, the welding process can be performed so that the welding lines L do not overlap and are connected continuously when welding in multiple spiral patterns 140, 150.
[0039] The multiple spiral patterns 140, 150 may include a first spiral pattern 140 and a second spiral pattern 150.
[0040] Here, the welding process can begin at the center 141 of the first spiral pattern 140 and end at the center 151 of the second spiral pattern 150.
[0041] The welding process can be performed by irradiating the substrate 130 with a laser device. Here, the welding process can be performed, for example, by irradiating the substrate 130 with a laser device having a wavelength of 1030 nm to 1070 nm. Therefore, by irradiating the substrate 130 with a laser having a wavelength of 1030 nm to 1070 nm, it can be ensured that the weld quality can withstand the high separation load that would separate multiple welded substrates 130.
[0042] During the welding process, a first spiral pattern 140 can be formed by irradiating the laser in a counterclockwise direction, and a second spiral pattern 150 can be formed by irradiating the laser in a clockwise direction. That is, during the welding process, the welding pattern 160 can form a first spiral pattern 140 pointing from the inside to the outside, and then connect the welding line L to form a second spiral pattern 150 pointing from the outside to the inside.
[0043] The welding line L may include a first welding line La of a first spiral pattern 140, a second welding line Lb of a second spiral pattern 150, and a third welding line Lc connecting the first spiral pattern 140 and the second spiral pattern 150. Here, the first welding line La and the second welding line Lb may be formed as curves to form a spiral pattern, and the second welding line Lb may be formed as a straight line to connect the first welding line La and the second welding line Lb.
[0044] Simultaneously, the welding process can be performed such that the diameters R1 and R2 of the multiple spiral patterns 140 and 150 are all formed to be between 1.5π and 3.0π. That is, the welding process can be performed such that the diameter R1 of the first spiral pattern 140 and the diameter R2 of the second spiral pattern 150 are each between 1.5π and 3.0π. Therefore, the first spiral pattern 140 and the second spiral pattern 150 are welded to have diameters R1 and R2 respectively at the level of 1.5π to 3.0π, resulting in the effect that they can function as effective welding patterns 160 from both a mechanical and material point of view within a narrow area. At this time, the diameters R1 of the first spiral pattern 140 and R2 of the second spiral pattern 150 are formed to be equal to or greater than 1.5π as a lower limit, resulting in the effect of preventing excessive heat input due to the superposition of heat input along the welding line L in the direction from the outside to the inside (outside → inside) of the spiral patterns 140 and 150.
[0045] Simultaneously, the welding process can be performed such that the intervals d1 and d2 between the welding lines L in the plurality of spiral patterns 140 and 150 are 0.2 mm to 0.4 mm. That is, the welding process can be performed such that the intervals d1 and d2 between the welding lines L in the first spiral pattern 140 and the second spiral pattern 150 are 0.2 mm to 0.4 mm. Therefore, the intervals d1 and d2 between the welding lines L in the first spiral pattern 140 and the second spiral pattern 150 are formed to be equal to or greater than the lower limit of 0.2 mm, and thus have the effect of preventing the strength of the welded portion from decreasing due to excessive heat input when the intervals d1 and d2 between the welding lines L are too narrow. Additionally, the intervals d1 and d2 between the welding lines L in the first spiral pattern 140 and the second spiral pattern 150 are formed to be equal to or less than the upper limit of 0.4 mm, and thus have the effect of preventing the formation of a weaker welded portion when the intervals d1 and d2 between the welding lines L are too wide.
[0046] Figure 3 This is a perspective view showing an example of a welded product welded by a welding method according to an embodiment of the present disclosure.
[0047] At the same time, refer to Figure 3 The multiple substrates 130 can be electrode leads E and busbars B in the battery module. The battery module includes a unit stack and a busbar B. Multiple secondary batteries 10 are stacked in the unit stack. The multiple secondary batteries 10 have electrode leads E, and the busbar B connects the electrode leads E of the multiple secondary batteries 10.
[0048] In the welding method according to the embodiments of the present disclosure configured as described above, when a welding pattern 160 is formed by welding multiple substrates together in the form of multiple spiral patterns 140, 150 connected together, continuous welding without overlapping of the welding lines L can reduce spatter, improve mechanical properties, improve space utilization, and increase the possibility of real-time welding quality inspection. That is, when a spiral pattern is formed, a large amount of spatter is generated at the welding start point and a large amount of cracks are generated at the welding end point. However, the welding method according to the embodiments of the present disclosure can form the welding pattern 160 in the form of multiple spiral patterns connected together, thereby significantly reducing spatter generated at the welding start point and cracks generated at the welding end point.
[0049] Additionally, in the welding method according to embodiments of the present disclosure, the welding lines L of the plurality of spiral patterns 140, 150 can be welded continuously without overlapping, thereby preventing defects in the welded portion due to high heat and overheating generated when the welding lines L overlap. Furthermore, the notch effect that occurs when the plurality of spiral patterns 140, 150 each form a single pattern can be significantly reduced. Additionally, the notch effect at corners can be prevented when welding with rectangular patterns. In other words, the notch effect can be eliminated to improve mechanical properties under repeated loads.
[0050] Furthermore, in the welding method according to embodiments of this disclosure, the plurality of spiral patterns 140, 150 include a first spiral pattern 140 and a second spiral pattern 150, and the welding begins at the center 141 of the first spiral pattern 140 and ends at the center 151 of the second spiral pattern 150, such that the two spiral patterns 140, 150 can form a non-overlapping continuous pattern, thereby ensuring mechanical properties capable of withstanding similar loads even when the diameter of the welded portion (weld pattern) is reduced. Therefore, space utilization can be improved, and the possibility of real-time weld quality inspection can be increased. That is, compared to forming two spiral patterns individually, when the two spiral patterns 140, 150 form a non-overlapping continuous pattern, the weld length is increased, and therefore mechanical properties capable of withstanding similar loads can be ensured even when the diameter is reduced (weld length increased by 41.1%).
[0051] Welding products according to the embodiments
[0052] The welding products according to embodiments of the present disclosure will be described below.
[0053] Reference Figure 1 According to embodiments of the present disclosure, a welding product 100 includes: a plurality of substrates 130 positioned to overlap each other; and a predetermined welding pattern 160 formed by welding the plurality of substrates 130 together.
[0054] The welding product 100 according to the embodiments of this disclosure relates to a welding product 100 manufactured by the welding method described in the above embodiments. Therefore, in this embodiment, content that is repeated in the above embodiments will be omitted or briefly described, and the differences will be mainly described.
[0055] More specifically, the welding pattern 160 forms multiple spiral patterns. Here, the welding lines L of the multiple spiral patterns 140, 150 do not overlap and are connected. At this time, the welding lines L of the multiple spiral patterns 140, 150 may not overlap and may be continuous. The multiple spiral patterns may include a first spiral pattern 140 and a second spiral pattern 150.
[0056] The welding line L may have a welding start point located at the center 141 of the first spiral pattern 140 and a welding end point located at the center 151 of the second spiral pattern 150.
[0057] In other words, the welding pattern 160 can form a welding line L that starts at the center 141 of the first spiral pattern 140 and ends at the center 151 of the second spiral pattern 150.
[0058] The welding line L may include a first welding line La of a first spiral pattern 140, a second welding line Lb of a second spiral pattern 150, and a third welding line Lc connecting the first spiral pattern 140 and the second spiral pattern 150. Here, the first welding line La and the second welding line Lb may be formed as curves to form a spiral pattern, and the second welding line Lb may be formed as a straight line to connect to the first welding line La and the second welding line Lb.
[0059] The width w1 of the overlapping portion of the multiple substrates 130 can be from 8 mm to 15 mm.
[0060] Here, the plurality of substrates 130 may include a first substrate 110 and a second substrate 120, and the width of the overlapping portion of the first substrate 110 and the second substrate 120 may be, for example, 8 mm to 15 mm.
[0061] Simultaneously, the diameters of the multiple spiral patterns 140 and 150 can each be formed to be between 1.5π and 3.0π. That is, the first spiral pattern 140 and the second spiral pattern 150 can be welded to have diameters of 1.5π to 3.0π respectively. Therefore, the first spiral pattern 140 and the second spiral pattern 150 are welded to have diameters at the level of 1.5π to 3.0π, which has the effect that they can serve as effective weld patterns 160 from both a mechanical and material perspective within a narrow area. At this time, the diameters of the first spiral pattern 140 and the second spiral pattern 150 are formed to be equal to or greater than 1.5π as the lower limit, which has the effect of preventing excessive heat input due to the superposition of heat input along the weld line L in the direction from the outside to the inside (outside to inside) of the spiral patterns 140 and 150.
[0062] Simultaneously, the intervals d1 and d2 between the welding lines L in the plurality of spiral patterns 140 and 150 can be from 0.2 mm to 0.4 mm. That is, the first spiral pattern 140 and the second spiral pattern 150 can be welded such that the intervals d1 and d2 between the welding lines L are from 0.2 mm to 0.4 mm. Therefore, the intervals d1 and d2 between the welding lines L in the first spiral pattern 140 and the second spiral pattern 150 are formed to be equal to or greater than the lower limit of 0.2 mm, and thus have the following effect: preventing the strength of the welded portion from decreasing due to excessive heat input when the intervals d1 and d2 between the welding lines L are too narrow. Additionally, the intervals d1 and d2 between the welding lines L in the first spiral pattern 140 and the second spiral pattern 150 are formed to be equal to or less than the upper limit of 0.4 mm, and thus have the following effect: preventing the formation of a weaker welded portion when the intervals d1 and d2 between the welding lines L are too wide.
[0063] Figure 4 This is an exemplary plan view showing a welded portion of a welded product welded by a welding method according to an embodiment of the present disclosure. Figure 5 This is an enlarged plan view showing a welded portion of another example of a welded product welded by a welding method according to an embodiment of the present disclosure. Figure 6 This shows a cross-sectional view of a secondary battery, another example of the secondary battery being applied to a welded product welded using a welding method according to embodiments of this disclosure, and... Figure 7 This is a perspective view showing another example of a welded product welded by a welding method according to an embodiment of the present disclosure.
[0064] Additionally, see reference Figures 3 to 7 The multiple substrates 130 can be electrode terminals T, T' and busbars B, B' in the battery module. The battery module includes unit components S, S' and busbars B, B'. Multiple secondary batteries 10, 10' are arranged in the unit components. The multiple secondary batteries have electrode terminals, and the busbars B, B' connect the electrode terminals T, T' of the multiple secondary batteries 10, 10'.
[0065] Meanwhile, as an example, refer to Figure 3 and Figure 4The secondary battery 10 can be configured as a pouch-type secondary battery 10, wherein the electrode assembly is housed within a pouch-shaped member 11. Here, the electrode terminal T may include an electrode lead E, which connects to the electrode assembly and extends to the outside of the pouch-shaped member 11. In this case, multiple substrates 130 may include the electrode lead E. Furthermore, for example, the width w1 of the overlapping portion of the electrode lead E (as the first substrate) and the busbar B (as the second substrate) may be 8 mm to 15 mm. Specifically, for example, the width w1 of the overlapping portion of the electrode lead E (as the first substrate) and the busbar B (as the second substrate) may be 8 mm to 15 mm. Furthermore, the busbar B may include various shapes, such as a straight portion or a "ㅁ"-shaped portion with a busbar hole B1 formed in the center.
[0066] Meanwhile, as another example, refer to Figures 5 to 7 The secondary battery 10' can be configured as a cylindrical secondary battery 10', in which the electrode assembly A is housed in the can-shaped member 20'. The electrode terminal T' may include: a positive terminal T1', positioned at the center of the outer end of the can-shaped member 20'; and a negative terminal T2', positioned around the positive terminal T1' at the outer end of the can-shaped member 20'. Here, the plurality of substrates 130 may include the positive terminal T1' and the negative terminal T2'. Furthermore, the width w2 of the overlapping portion of the electrode terminal T' as the first substrate and the busbar B' as the second substrate may be 8 mm to 15 mm. In this case, the positive terminal T1' may be connected to the positive electrode contact 12, which extends from the positive electrode of the electrode assembly A, and the negative terminal T2' may be connected to the negative electrode contact 13, which extends from the negative electrode of the electrode assembly A.
[0067] Battery module according to the implementation method
[0068] At the same time, refer to Figure 1 , Figure 3 , Figure 5 and Figure 7 The battery modules M and M' can be constructed in the following manner: including welded products 100 and 100' constructed according to embodiments of the present disclosure as described above.
[0069] The welded products 100 and 100' include: a plurality of substrates 130 positioned to overlap each other; and a predetermined weld pattern 160 formed by welding the plurality of substrates 130 together, wherein the weld pattern 160 forms a plurality of spiral patterns 140 and 150, and the weld lines L of the plurality of spiral patterns 140 and 150 do not overlap and are continuous.
[0070] Here, the multiple substrates 130 can be electrode terminals T, T' and busbars B, B' in battery modules M, M'. The battery modules M, M' include unit components S, S' and busbars B, B'. Multiple secondary batteries 10, 10' are arranged in the unit components S, S'. The multiple secondary batteries 10, 10' have electrode terminals T, T', and the busbars B, B' connect the electrode terminals T, T' of the multiple secondary batteries 10, 10'.
[0071] In other words, the battery modules M and M' may include the unit components S and S' in which the secondary batteries 10 and 10' are arranged, as well as the welded products 100 and 100', and the welded products 100 and 100' may include the electrode terminals T and T' as the first substrate 110, the busbars B and B' as the second substrate 120, and the welded pattern 160.
[0072] <Manufacturing Example>
[0073] Multiple substrates 130 are welded together to form a welding pattern 160 in the form of multiple spiral patterns being connected, and a welded product is manufactured by continuously welding in the form of multiple spiral patterns without overlapping the welding lines.
[0074] At this point, the diameter D2 of the spiral pattern is formed to be 2.3π.
[0075] Here, the plurality of substrates 130 include a first substrate 110 made of aluminum and a second substrate 120 made of steel.
[0076] Furthermore, the welding pattern 160 is formed by laser welding. At this time, the laser power is 550 W and the welding speed is 300 mm / s.
[0077] <Comparison Example>
[0078] The welded product is manufactured by welding multiple substrates 130 together, such that multiple spiral patterns each form a separate weld pattern P without connecting the multiple spiral patterns.
[0079] At this point, the diameter D1 of the spiral pattern is formed to be 3.0π. Here, multiple substrates 130 are used as the same items as those in the manufacturing example. Furthermore, the welding pattern 160 is formed by laser welding as in the manufacturing example. At this point, the laser power is 600 W, and the welding speed is 300 mm / s.
[0080] Figure 8 This is an external photograph showing the fracture state of a welded product welded according to the welding method of the comparative example, and Figure 9 This is an external photograph showing the fracture state of a welded product welded according to a welding method based on a manufacturing example. Here, Figure 8 and Figure 9 This is a photograph showing the state in which the second substrate 120 breaks due to the tensile load applied to the first substrate 110. At this time, Figure 8 and Figure 9 The diagram shows a state in which the first substrate 110 and the second substrate 120 are broken around the weld pattern P, 160 and broken to each other along the break lines L1, L2, which are formed along the outer lines of the weld pattern P, 160.
[0081] Additionally, Figure 10 It shows a graph of the tensile load of a welded product welded according to the welding method of the comparative example, and Figure 11 It is a graph showing the tensile load of a welded product welded according to the welding method of the manufacturing example.
[0082] <Experimental Example>
[0083] Welded products of a manufacturing example and a comparative example were manufactured respectively. Tensile force was applied to the welded products in which multiple substrates 130 were welded together, causing them to fracture and separate. The maximum tensile load at fracture was measured, and then... Figure 10 The graph shows the results of the manufacturing example, and in Figure 11 The graph shows the results of the comparison examples.
[0084] Furthermore, welded products of the manufacturing example and the comparative example were manufactured separately, and tensile loads were applied to measure the tensile load at fracture. The fractured substrate 130 was then welded again to measure the tensile load of the welded product. This process was repeated several times, and the results were obtained in… Figure 10 and Figure 11 It is shown in the middle.
[0085] Here, in Figure 10 and Figure 11 In the figure, the unit of the vertical axis is load [N], which represents tension, and the unit of the horizontal axis is displacement [mm], which represents displacement. Figure 10 It shows that when by according to Figure 8 The graph shows the maximum tensile load at fracture of welded product A, which is a comparative example of the welding method shown. Figure 11 It shows that when by according to Figure 9 The graph shows the maximum tensile load at the point of fracture of welded product B, which is produced using the welding method shown in the manufacturing example.
[0086] It can be seen that, as Figure 10 As shown, the average maximum tensile load of welded product A in the comparative example is approximately 1000 N, and as... Figure 11As shown, the maximum tensile load of the welded product B in the manufacturing example is approximately 1033 N on average.
[0087] Therefore, it can be seen that the maximum tensile load is similar when the weld pattern P of the comparative example is formed as individual spiral patterns with a diameter D1 of 3.0 π during welding, and when the weld pattern 160 of the manufacturing example is formed as a connection of two non-overlapping spiral patterns with a diameter D2 of 2.3 π.
[0088] Therefore, when two spiral patterns are formed without overlapping during welding as in the manufacturing example, the maximum tensile load is similar, although it is smaller than the spiral pattern formed by each individual spiral pattern in the comparative example, and thus it can be seen that, under the appropriate maximum tensile load, the size of the weld pattern 160 can be reduced as in the manufacturing example.
[0089] Finally, it can be seen that forming the welding pattern 160 with two non-overlapping spiral patterns in the manufacturing example has the effect of ensuring the following mechanical properties: even when the size of the welding pattern 160 is reduced compared to forming two welding patterns P with one spiral pattern in the comparative example, it can still ensure mechanical properties that can withstand similar loads.
[0090] The present disclosure has been described in detail above through specific embodiments, but this is intended to specifically describe the present disclosure, and the present disclosure is not limited thereto. It can be said that various modifications and changes can be made by those skilled in the art within the technical concept of the present disclosure.
[0091] Furthermore, the specific scope of protection of this disclosure will become clear from the appended claims of this patent.
[0092] List of reference numerals
[0093] 10, 10': Secondary battery
[0094] 11: Bag-shaped items
[0095] 100, 100': Welding products
[0096] 110: First substrate
[0097] 120: Second substrate
[0098] 130: Substrate
[0099] 140: First spiral pattern
[0100] 141: Center
[0101] 150: Second spiral pattern
[0102] 151: Center
[0103] 160: Welding pattern
[0104] B, B': Busbar
[0105] B1: Busbar opening
[0106] E: Electrode lead
[0107] S, S': Unit components
[0108] C: Central side
[0109] T, T': Electrode terminals
[0110] T1, T1': Negative extreme sub-particles
[0111] T2, T2': Positive extreme sub-particles
[0112] G: Pattern extension (length) direction
[0113] W: Pattern width direction
[0114] w1, w2: Width
Claims
1. A welding method, comprising: The positioning process involves positioning multiple substrates to overlap each other. as well as The welding process involves welding the plurality of substrates together to form a predetermined welding pattern. The welding process involves welding the welding pattern by connecting multiple non-overlapping spiral patterns.
2. The welding method according to claim 1, in, The welding process is performed such that when welding in the plurality of spiral patterns, the weld lines do not overlap and are continuously connected.
3. The welding method according to claim 2, in, The plurality of spiral patterns include a first spiral pattern and a second spiral pattern, and The welding process begins at the center of the first spiral pattern and ends at the center of the second spiral pattern.
4. The welding method according to claim 3, in, The welding process is performed by using a laser device to irradiate the substrate with a laser.
5. The welding method according to claim 4, in, During the welding process, The first spiral pattern is formed by irradiating the laser in a counterclockwise direction, and The second spiral pattern is formed by irradiating the laser in a clockwise direction.
6. The welding method according to claim 1, in, During the positioning process, the plurality of substrates are positioned such that the width of the overlapping portion is 8 mm to 15 mm.
7. The welding method according to claim 1, in, The plurality of substrates are electrode terminals and busbars in a battery module. The battery module includes a unit assembly and the busbar. A plurality of secondary batteries are arranged in the unit assembly. The plurality of secondary batteries have the electrode terminals, and the busbar connects the electrode terminals of the plurality of secondary batteries.
8. The welding method according to claim 1, in, The welding process is performed such that the diameters of the plurality of spiral patterns are each formed to be between 1.5π and 3.0π.
9. The welding method according to claim 2, in, The welding process is performed such that the spacing between the welding lines in the plurality of spiral patterns is 0.2 mm to 0.4 mm.
10. The welding method according to claim 1, in, The welding process is performed by irradiating the substrate with a laser with a wavelength of 1030 nm to 1070 nm using the laser device.
11. A welding product, comprising: Multiple substrates, wherein the multiple substrates are positioned to overlap each other; as well as A predetermined welding pattern, which is formed by welding the plurality of substrates together. The welding pattern forms multiple spiral patterns, and The multiple spiral patterns do not overlap and are connected.
12. The welded product according to claim 11, in, The welding lines of the multiple spiral patterns do not overlap and are continuously connected.
13. The welded product according to claim 12, in, The plurality of spiral patterns include a first spiral pattern and a second spiral pattern, and The welding line has a welding start point located at the center of the first spiral pattern and a welding end point located at the center of the second spiral pattern.
14. The welded product according to claim 11, in, The width of the overlapping portion of the plurality of substrates is 8 mm to 15 mm.
15. The welded product according to claim 11, in, The plurality of substrates are electrode terminals and busbars in a battery module. The battery module includes a unit assembly and the busbar. A plurality of secondary batteries are arranged in the unit assembly. The plurality of secondary batteries have electrode terminals, and the busbar connects the electrode terminals of the plurality of secondary batteries.
16. The welded product according to claim 15, in, The secondary battery is configured as a pouch-type secondary battery, in which the electrode assembly is housed within a pouch-like structure. The electrode terminals include electrode leads that are connected to the electrode assembly and extend to the outside of the pouch-like member. The plurality of substrates include the electrode leads.
17. The welded product according to claim 15, in, The secondary battery is configured as a cylindrical secondary battery, in which the electrode assembly is housed within a can-shaped component. The electrode terminals include: a positive terminal positioned at the center of the outer end of the can-shaped member; and a negative terminal positioned around the positive terminal at the outer end of the can-shaped member. The plurality of substrates includes the positive terminal and the negative terminal.
18. The welded product according to claim 11, in, The diameters of the plurality of spiral patterns are each between 1.5π and 3.0π.
19. The welded product according to claim 12, in, The spacing between the welding lines in the plurality of spiral patterns is 0.2 mm to 0.4 mm.
20. A battery module comprising a welded product according to any one of claims 11 to 19.