System and method for gap control for high quality bus welds

Abstract

Systems and methods for gap control of high quality busbar welds are disclosed. The system includes a busbar having a top surface and a bottom surface opposite the top surface, a terminal including a top surface and a bottom surface opposite the top surface, two or more welds applied to one of the top surface of the terminal or the bottom surface of the busbar, the two or more welds extending to a height of between 0.1 mm and 0.2 mm and configured to maintain a gap of between 0.1 mm and 0.2 mm in a subsequent weld area between the bottom surface of the busbar and the top surface of the terminal when the bottom surface of the busbar and the top surface of the terminal are mated, and one or more welds applied to the busbar and the terminal to secure the busbar to the terminal.

Description

[0001] The information provided in this section is for the purpose of presenting the general background of this disclosure. The work of the currently named inventors, to the extent described in this section, and in all aspects of that description which at the time of filing may not be regarded as prior art, is neither expressly nor implicitly considered prior art to this disclosure. Technical Field

[0002] This disclosure primarily relates to systems and methods for gap control in quality busbar welds. Porosity is a common problem in aluminum busbar welding, mainly due to the presence of low-boiling-point materials, such as surface contaminants. When welding is performed under zero-gap conditions, vapors generated from low-boiling-point materials become trapped, leading to the formation of micropores in the weld. However, vapors can escape freely by introducing small gaps of approximately 0.1–0.2 mm. The welding process becomes more stable, and the metallurgical micropores in the weld are significantly reduced, resulting in increased weld strength and greater consistency. Summary of the Invention

[0003] This section provides a general summary of the inventive methods and approaches associated with this disclosure, and is not a full disclosure of its entire scope or all its features.

[0004] One aspect of this disclosure provides a system including a busbar, a terminal, and one or more weld portions. The busbar includes a top surface and a bottom surface opposite to the top surface. The terminal includes a top surface and a bottom surface opposite to the top surface. The terminal includes a first weld portion applied to the top surface of the terminal and a second weld portion applied to the top surface of the terminal. The first weld portion extends beyond the top surface of the terminal to a height between 0.1 mm and 0.2 mm. The second weld portion extends beyond the top surface of the terminal to a height between 0.1 mm and 0.2 mm. The first and second weld portions are configured to maintain a gap between 0.1 mm and 0.2 mm in a subsequently welded area between the bottom surface of the busbar and the top surface of the terminal when the bottom surface of the busbar mates with the top surface of the terminal. One or more weld portions are applied to the busbar and the terminal to secure the busbar to the terminal.

[0005] Embodiments of this disclosure may include one or more of the following optional features. In some embodiments, the first weld and the second weld are joint welds that are straight lines or curves.

[0006] The first and second welding parts can be spot welded parts.

[0007] The system may include a third weld portion applied to the top surface of the terminal and a fourth weld portion applied to the top surface of the terminal, the third weld portion extending beyond the top surface of the terminal to a height between 0.1 mm and 0.2 mm, and the fourth weld portion extending beyond the top surface of the terminal to a height between 0.1 mm and 0.2 mm. The third and fourth weld portions may be spot weld portions.

[0008] The height of the first weld and the height of the second weld can be based on the power applied by the laser welding machine.

[0009] The first and second weld portions can be applied to the terminal during laser cutting.

[0010] The first and second welding parts can be applied to the terminals just before they are welded to the busbar.

[0011] Another aspect of this disclosure provides a system comprising a busbar, a terminal, two or more weld portions, and one or more weld portions, the busbar including a top surface and a bottom surface opposite to the top surface, the terminal including a top surface and a bottom surface opposite to the top surface, the two or more weld portions being applied to one of the top surface of the terminal or the bottom surface of the busbar, the two or more weld portions extending to a height between 0.1 mm and 0.2 mm, and configured to maintain a gap between 0.1 mm and 0.2 mm in a subsequent weld area between the bottom surface of the busbar and the top surface of the terminal when the bottom surface of the busbar mates with the top surface of the terminal, the one or more weld portions being applied to the busbar and the terminal to secure the busbar to the terminal.

[0012] Embodiments of this disclosure may include one or more of the following optional features. In some embodiments, two or more welded portions are straight lines or curved joint welded portions.

[0013] Two or more welded parts can be spot welded parts.

[0014] Two or more welded sections include four welded sections.

[0015] The height of two or more welded sections can be based on the power applied by the laser welding machine.

[0016] Two or more welds can be applied to one of the terminals or busbars during laser cutting.

[0017] Two or more solder joints can be applied to one of the terminals or busbars just before the terminal is soldered to the busbar.

[0018] Another aspect of this disclosure provides a method comprising providing a busbar, providing a terminal, applying two or more solder joints to a top surface of the terminal or one of the top surfaces of the terminal, and applying one or more solder joints to the busbar and the terminal to secure the busbar to the terminal. The busbar includes a top surface and a bottom surface opposite to the top surface, the terminal includes a top surface and a bottom surface opposite to the top surface, the two or more solder joints extend to a height between 0.1 mm and 0.2 mm, and are configured to maintain a gap between the bottom surface of the busbar and the top surface of the terminal when the bottom surface of the busbar mates with the top surface of the terminal.

[0019] Embodiments of this disclosure may include one or more of the following optional features. In some embodiments, two or more welded portions are straight lines or curved joint welded portions.

[0020] Two or more welded parts can be spot welded parts.

[0021] Two or more welded sections can include four welded sections.

[0022] The height of two or more welded sections can be based on the power applied by the laser welding machine.

[0023] The present invention also discloses the following technical solutions:

[0024] Option 1. A system comprising:

[0025] A busbar, the busbar including a top surface and a bottom surface opposite the top surface;

[0026] A terminal, the terminal including a top surface and a bottom surface opposite the top surface of the terminal, the terminal including a first weld portion applied to the top surface of the terminal and a second weld portion applied to the top surface of the terminal, the first weld portion extending beyond the top surface of the terminal to a height between 0.1 mm and 0.2 mm, the second weld portion extending beyond the top surface of the terminal to a height between 0.1 mm and 0.2 mm, the first weld portion and the second weld portion being configured to maintain a gap between 0.1 mm and 0.2 mm in a subsequently welded area between the bottom surface of the busbar and the top surface of the terminal when the bottom surface of the busbar mates with the top surface of the terminal; and

[0027] One or more welds are applied to the busbar and the terminal to secure the busbar to the terminal.

[0028] Option 2. The system according to Option 1, wherein the first weld and the second weld are joint welds that are straight lines or curves.

[0029] Option 3. The system according to Option 1, wherein the first welding part and the second welding part are spot welding parts.

[0030] Option 4. The system according to Option 1 further includes a third weld portion applied to the top surface of the terminal and a fourth weld portion applied to the top surface of the terminal, the third weld portion extending beyond the top surface of the terminal to a height between 0.1 mm and 0.2 mm, and the fourth weld portion extending beyond the top surface of the terminal to a height between 0.1 mm and 0.2 mm.

[0031] Option 5. The system according to Option 4, wherein the third welding part and the fourth welding part are spot welding parts.

[0032] Option 6. The system according to Option 1, wherein the height of the first weld and the height of the second weld are based on the power applied by the laser welding machine.

[0033] Option 7. The system according to Option 1, wherein the first weld and the second weld are applied to the terminal during laser cutting of the terminal.

[0034] Option 8. The system according to Option 1, wherein the first welding portion and the second welding portion are applied to the terminal before the terminal is welded to the busbar.

[0035] Option 9. A system comprising:

[0036] A busbar, the busbar including a top surface and a bottom surface opposite the top surface;

[0037] A terminal, the terminal including a top surface and a bottom surface opposite the top surface of the terminal;

[0038] Two or more weld portions are applied to one of the top surface of the terminal or the bottom surface of the busbar, the weld portions extending to a height between 0.1 mm and 0.2 mm, and configured to maintain a gap between 0.1 mm and 0.2 mm in a subsequent weld area between the bottom surface of the busbar and the top surface of the terminal when the bottom surface of the busbar mates with the top surface of the terminal; and

[0039] One or more welds are applied to the busbar and the terminal to secure the busbar to the terminal.

[0040] Option 10. The system according to Option 9, wherein the two or more welded portions are straight or curved joint welded portions.

[0041] Option 11. The system according to Option 9, wherein the two or more welded parts are spot welded parts.

[0042] Option 12. The system according to Option 9, wherein the two or more welded portions include four welded portions.

[0043] Option 13. The system according to Option 9, wherein the height of the two or more welded portions is based on the power applied by the laser welding machine.

[0044] Option 14. The system according to Option 9, wherein the two or more welds are applied to one of the terminals or the busbar during laser cutting of the terminal or busbar.

[0045] Option 15. The system according to Option 9, wherein the two or more solder joints are applied to one of the terminals or the busbar before the terminals are soldered to the busbar.

[0046] Option 16. A method comprising:

[0047] A busbar is provided, the busbar including a top surface and a bottom surface opposite the top surface;

[0048] A terminal is provided, the terminal including a top surface and a bottom surface opposite the top surface of the terminal;

[0049] Two or more weld joints are applied to one of the top surface of the terminal or the bottom surface of the busbar, the two or more weld joints extending to a height between 0.1 mm and 0.2 mm, and configured to maintain a gap between the bottom surface of the busbar and the top surface of the terminal when the bottom surface of the busbar mates with the top surface of the terminal; and

[0050] One or more welds are applied to the busbar and the terminal to secure the busbar to the terminal.

[0051] Option 17. The method according to Option 16, wherein the two or more welded portions are straight or curved joint welded portions.

[0052] Option 18. The method according to Option 16, wherein the two or more welded portions are spot welded portions.

[0053] Option 19. The method according to Option 16, wherein the two or more welded portions include four welded portions.

[0054] Option 20. The method according to Option 16, wherein the height of the two or more welded portions is based on the power applied by the laser welding machine.

[0055] Further areas of application will become apparent from the description provided herein. The descriptions and specific examples in this invention are for illustrative purposes only and are not intended to limit the scope of this disclosure. Attached Figure Description

[0056] The accompanying drawings described herein are for illustrative purposes only for the selected configurations and are not intended to limit the scope of this disclosure.

[0057] Figure 1 It is a perspective view of busbars and terminals according to the principles of this disclosure, including pre-treated laser welds;

[0058] Figure 2 yes Figure 1 A cross-sectional view of the terminal, including the pre-treated laser weld;

[0059] Figure 3 yes Figure 1 A cross-sectional view of the busbar, which is welded to the terminal while maintaining the gap defined by the pre-treated laser weld.

[0060] Figure 4 This is a perspective view of another terminal, which includes a pre-treated laser solder joint;

[0061] Figure 5 This is a perspective view of another terminal, which includes a pre-treated laser solder joint;

[0062] Figure 6 This is a perspective view of the busbar and terminals, including pre-treated laser welds on the busbar.

[0063] Figure 7 yes Figure 6 A cross-sectional view of the busbar, wherein the pre-treated laser weld is adjacent to the terminal while maintaining the gap defined by the pre-treated laser weld;

[0064] Figure 8A It is a perspective view including the generatrix of the protrusions;

[0065] Figure 8B It includes protrusions Figure 8A A cross-sectional view of the busbar;

[0066] Figure 9 yes Figure 8A A cross-sectional view of the busbar, which includes protrusions welded to the terminals while maintaining a gap defined by the protrusions;

[0067] Figure 10 It is a graph comparing the strength of the weld between the terminal and the busbar with the nominal gap defined by the pre-treated laser weld or protrusion; and

[0068] Figure 11 It is a chart showing the height of the laser weld as a function of the laser power.

[0069] The corresponding reference numerals throughout the figures indicate the corresponding components. Detailed Implementation

[0070] Example configurations will now be described more fully with reference to the accompanying drawings. Example configurations are provided to make this disclosure exhaustive and to fully convey the scope of this disclosure to those skilled in the art. Specific details are set forth, such as examples of specific parts, apparatus, and methods, to provide a thorough understanding of the configurations of this disclosure. It will be apparent to those skilled in the art that specific details are not required, example configurations may be embodied in many different forms, and the specific details and example configurations should not be construed as limiting the scope of this disclosure.

[0071] The terminology used herein is for the purpose of describing particular example configurations only and is not intended to be limiting. As used herein, the singular articles “a,” “an,” and “the” may also be intended to include the compound forms, unless the context clearly indicates otherwise. The terms “comprising,” “including,” “containing,” and “having” are inclusive and therefore indicate the presence of features, steps, operations, elements, and / or parts, but do not exclude the presence or addition of one or more other features, steps, operations, elements, parts, and / or groups thereof. The method steps, processes, and operations described herein should not be construed as necessarily requiring them to be performed in the particular order discussed or shown, unless specifically indicated as such. Additional or alternative steps may be employed.

[0072] When an element or layer is referred to as being "on," "joined to," "connected to," "attached to," or "linked to" another element or layer, it can be directly on, directly joined to, directly connected to, directly attached to, or directly linked to the other element or layer, or an intervening element or layer may be present. Conversely, when an element is referred to as being "directly on," "directly joined to," "directly connected to," directly attached to, or directly linked to another element or layer, an intervening element or layer may not be present. Other terms used to describe the relationship between elements should be interpreted in a similar manner (e.g., contrast between "between" and "directly between," contrast between "adjacent" and "directly adjacent," etc.). As used herein, the term "and / or" includes any and all combinations of one or more of the related listed items.

[0073] The terms “first,” “second,” “third,” etc., may be used herein to describe various elements, parts, regions, layers, and / or sections. These elements, parts, regions, layers, and / or sections should not be limited by these terms. These terms may be used only to distinguish one element, part, region, layer, or section from another. Terms such as “first,” “second,” and other numerical terms do not imply order or sequence unless explicitly indicated by the context. Therefore, the first element, part, region, layer, or section discussed below may be referred to as the second element, part, region, layer, or section without departing from the teachings of the example configuration.

[0074] refer to Figure 1 The diagram shows a busbar 100 and a terminal 200. The busbar 100 and terminal 200 are configured to be soldered to each other for any suitable application, including but not limited to any suitable electrical application. The terminal 200 may include a contact portion 300 for transmitting electrical energy or a signal from a power source. The busbar 100 may include a top surface 100a and a bottom surface 100b. The busbar 100 may have any suitable size or shape. The terminal 200 may include a top surface 200a and a bottom surface 200b. The terminal 200 may have any suitable size and shape.

[0075] Terminal 200 may include one or more laser weld seams 202a, 202b on top surface 200a. Laser weld seams 202a, 202b may be applied prior to bonding terminal 200 to busbar 100. In some embodiments, laser weld seams 202a, 202b may be formed using a laser beam while laser cutting terminal 200 and busbar 100. In other embodiments, laser weld seams 202a, 202b may be formed just before welding busbar 100 and terminal 200 together. Laser weld seams 202a, 202b can be straight or curved lines and can produce a raised weld top surface 0.1mm-0.2mm above top surface 200a of terminal 200. In this way, when the busbar 100 mates with the terminal 200, the laser welds 202a and 202b maintain a gap D of 0.1mm-0.2mm between the top surface 200a of the terminal 200 and the bottom surface 100b of the busbar 100. Figure 2 (See diagram in the middle).

[0076] With the maintained gap D, the busbar 100 can be welded to the terminal 100 via the welding portions 204a and 204b. Because of the gap D, vapors generated from the low-boiling-point material can escape freely, resulting in a more stable welding process and a significant reduction in metallurgical pores in the welding portion, thereby leading to increased weld strength and greater consistency.

[0077] Laser welds 202a and 202b can also be applied as one or more spot welds 202a, 202b, 202c, and 202d at any suitable location. For example, Figure 4 The image shows four spot-welded portions 202a, 202b, 202c, and 202d at the four corners of terminal 200. As another example, Figure 5 Two spot welded portions 202a and 202b are shown on either side of the contact portion 300. The spot welded portions can be of any suitable size and shape, such as circular, square, amorphous, etc.

[0078] refer to Figure 6 and Figure 7 The busbar 100 can be pre-treated with laser-welded sections 102a and 102b, which create a protruding bottom surface of the weld section 0.1mm-0.2mm below the bottom surface 100b of the busbar 100. In this way, when the busbar 100 mates with the terminal 200, the laser welds 102a and 102b maintain a gap D of 0.1mm-0.2mm between the top surface 200a of the terminal 200 and the bottom surface 100b of the busbar 100. Figure 7 (See diagram in the middle).

[0079] refer to Figure 8A and8B The busbar 100 may include protrusions 104a, 104b projecting from the bottom surface 100b, formed by stamping, hammering, or crimping the top surface 100a to create a recess in the top surface 100a and a corresponding protrusion in the bottom surface 100b. For example... Figure 9 As shown in the diagram, protrusions 104a and 104b maintain a gap D of 0.1mm-0.2mm between the top surface 200a of terminal 200 and the bottom surface 100b of busbar 100. Protrusions 104a and 104b can be of any suitable shape, such as straight, circular, or amorphous. In some embodiments, one or more spacers may be installed between busbar 100 and terminal 200 to maintain a gap between 0.1mm and 0.2mm.

[0080] refer to Figure 10 The diagram illustrates the strength of the weld between busbar 100 and terminal 200 at various gap distances between them. Data was collected across four different runs. As shown in the diagram, the strength is highest between 0.1 mm and 0.2 mm.

[0081] refer to Figure 11 The diagram illustrates the power required for a laser welding machine to produce a weld with a specific height. As explained in this article, the target height of the weld is between 0.1 mm and 0.2 mm. Figure 11 The data shown in the diagram is also presented in Table 1 below.

[0082] Table 1

[0083] Laser power (KW) Height of welded section (mm) 0.50 0.001872 1.00 0.003880 1.25 0.005564 1.50 0.016737 1.75 0.037342 2.00 0.051975 2.25 0.065113 2.50 0.088884 2.75 0.124502 3.00 0.108949

[0084] Numerous embodiments have been described. However, it should be understood that various modifications can be made without departing from the spirit and scope of this disclosure. Accordingly, other embodiments are within the scope of the following claims.

[0085] The foregoing description has been provided for illustrative and descriptive purposes. It is not intended to be exhaustive or limiting of this disclosure. Individual elements or features of a particular configuration are generally not limited to that particular configuration, but are interchangeable and can be used in selected configurations, if applicable, although not specifically illustrated or described. Identical items can also be modified in many ways. Such modifications are not considered to depart from this disclosure, and all such modifications are intended to be included within the scope of this disclosure.

Claims

1. A system comprising: A busbar, the busbar including a top surface and a bottom surface opposite the top surface; A terminal, the terminal including a top surface and a bottom surface opposite the top surface of the terminal, the terminal including a first weld portion applied to the top surface of the terminal and a second weld portion applied to the top surface of the terminal, the first weld portion extending beyond the top surface of the terminal to a height between 0.1 mm and 0.2 mm, the second weld portion extending beyond the top surface of the terminal to a height between 0.1 mm and 0.2 mm, the first weld portion and the second weld portion being configured to maintain a gap between 0.1 mm and 0.2 mm in a subsequently welded area between the bottom surface of the busbar and the top surface of the terminal when the bottom surface of the busbar mates with the top surface of the terminal; as well as One or more welds are applied to the busbar and the terminal to secure the busbar to the terminal.

2. The system according to claim 1, wherein the first weld and the second weld are joint welds that are straight lines or curves.

3. The system according to claim 1, wherein the first welding part and the second welding part are spot welding parts.

4. The system of claim 1, further comprising a third weld portion applied to the top surface of the terminal and a fourth weld portion applied to the top surface of the terminal, the third weld portion extending beyond the top surface of the terminal to a height between 0.1 mm and 0.2 mm, and the fourth weld portion extending beyond the top surface of the terminal to a height between 0.1 mm and 0.2 mm.

5. The system according to claim 4, wherein the third welding part and the fourth welding part are spot welding parts.

6. The system of claim 1, wherein the heights of the first weld and the second weld are based on the power applied by the laser welding machine.

7. The system of claim 1, wherein the first weld and the second weld are applied to the terminal during laser cutting of the terminal.

8. The system of claim 1, wherein the first welding portion and the second welding portion are applied to the terminal before the terminal is welded to the busbar.

9. A system comprising: A busbar, the busbar including a top surface and a bottom surface opposite the top surface; A terminal, the terminal including a top surface and a bottom surface opposite the top surface of the terminal; Two or more weld portions are applied to one of the top surface of the terminal or the bottom surface of the busbar, the two or more weld portions extending to a height between 0.1 mm and 0.2 mm, and configured to maintain a gap between 0.1 mm and 0.2 mm in the subsequent weld area between the bottom surface of the busbar and the top surface of the terminal when the bottom surface of the busbar mates with the top surface of the terminal; as well as One or more welds are applied to the busbar and the terminal to secure the busbar to the terminal.

10. A method, the method comprising: A busbar is provided, the busbar including a top surface and a bottom surface opposite the top surface; A terminal is provided, the terminal including a top surface and a bottom surface opposite the top surface of the terminal; Two or more welds are applied to one of the top surface of the terminal or the bottom surface of the busbar, the two or more welds extending to a height between 0.1 mm and 0.2 mm, and configured to maintain a gap between the bottom surface of the busbar and the top surface of the terminal when the bottom surface of the busbar mates with the top surface of the terminal; as well as One or more welds are applied to the busbar and the terminal to secure the busbar to the terminal.

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