Flexible circuit board with straight welding structure and integrated busbar

Abstract

The utility model discloses a flexible circuit board with a straight welding structure and an integrated busbar. The flexible circuit board comprises a copper layer, a first protective layer and a second protective layer. The copper layer is provided with a main body part and an epitaxial part which are integrally connected, the epitaxial part extends towards the outer side of a side line of the main body part, and a bonding pad area is arranged on the epitaxial part; the first protection layer covers the first surface of the copper layer, and a first windowing position is arranged at the position, matched with the bonding pad area, of the first protection layer; the second surface of the copper layer is covered with the second protection layer, a second windowing position is arranged at the position, matched with the bonding pad area, of the second protection layer, and the projection of at least one side edge of the second windowing position and the projection of at least one side edge of the first windowing position on the copper layer are mutually staggered. The main body part of the copper layer is provided with the extension part extending towards the outer side of the side line, and the extension part is provided with the bonding pad area, so that direct welding with aluminum palladium of the battery can be carried out through the bonding pad area of the extension part, a nickel sheet can be omitted, and the welding quality problem of the nickel sheet is avoided.

Description

Technical Field

[0001] This utility model relates to the field of circuit board technology, and in particular to a flexible circuit board with a direct-soldering structure and an integrated busbar. Background Technology

[0002] CCS (Cells Contact System), also known as a wiring harness board integration, is part of a battery management system and is used in fields such as new energy power batteries and energy storage batteries. Traditional CCSs typically use flexible circuit boards for signal acquisition, which are then connected to the battery's aluminum-palladium structure via nickel strips. However, soldering quality issues can easily arise between the flexible circuit board and the nickel strips, affecting the reliability of the CCS. Utility Model Content

[0003] This invention aims to solve at least one of the technical problems existing in the prior art. To this end, this invention proposes a flexible circuit board and integrated busbar with a direct-welding structure, which can directly weld to the aluminum-palladium of the battery without the need for nickel sheets.

[0004] On one hand, this utility model embodiment provides a flexible circuit board with a direct-soldering structure, comprising:

[0005] A copper layer having a main body and an epitaxial portion connected as one piece, the epitaxial portion extending outward from the edge of the main body, and having a pad area provided on the epitaxial portion;

[0006] A first protective layer covers the first surface of the copper layer, and the first protective layer is adapted to the position of the pad area to provide a first opening.

[0007] A second protective layer is provided on the second surface of the copper layer. The second protective layer is adapted to the position of the pad area and has a second window position. At least one edge of the second window position and the first window position are offset from each other on the projection of the copper layer.

[0008] According to some embodiments of the present invention, the width by which at least one edge of the second window position and the first window position is misaligned with each other on the projection of the copper layer is 0.5±0.01mm.

[0009] According to some embodiments of the present invention, at least one edge of the second window position and the first window position is provided with a wave structure.

[0010] According to some embodiments of the present invention, the edges of the second window position and the first window position that are offset from each other are provided with a wave structure.

[0011] According to some embodiments of the present invention, the thickness of the copper layer is 35 μm, the thickness of the first protective layer is 60 μm, and the thickness of the second protective layer is 50 μm.

[0012] According to some embodiments of the present invention, the widths of the first window position and the second window position are both greater than the width of the pad area.

[0013] On the other hand, this utility model embodiment provides a flexible circuit board with a direct-soldering structure, comprising:

[0014] A copper layer having a main body and an epitaxial portion connected as one piece, the epitaxial portion extending outward from the edge of the main body, and having a pad area provided on the epitaxial portion;

[0015] A first protective layer covers the first surface of the copper layer, and the first protective layer is adapted to the position of the pad area to provide a first opening.

[0016] A second protective layer is provided on the second surface of the copper layer. The second protective layer is adapted to the position of the pad area and has a second window. At least one edge of the second window and the first window is provided with a wave structure.

[0017] According to some embodiments of the present invention, the thickness of the copper layer is 35 μm, the thickness of the first protective layer is 60 μm, and the thickness of the second protective layer is 50 μm.

[0018] According to some embodiments of the present invention, the widths of the first window position and the second window position are both greater than the width of the pad area.

[0019] On another front, this utility model embodiment provides an integrated busbar, including the aforementioned flexible circuit board with a direct-soldering structure.

[0020] The embodiments of this utility model have at least the following beneficial effects:

[0021] An extension portion extending outward from the edge is provided in the main body of the copper layer, and a pad area is provided on the extension portion. The pad area of ​​the extension portion can be directly welded to the aluminum palladium of the battery, which can eliminate the need for nickel sheets and avoid the welding quality problems of nickel sheets. The first protective layer and the second protective layer can provide physical support and surface protection for the copper layer. The first protective layer and the second protective layer are respectively provided with a first window position and a second window position, which can expose the two opposite surfaces of the pad area, which facilitates ultrasonic welding of the pad area to aluminum palladium. The staggered edges of the first window position and the second window position or the setting of a wavy structure can prevent stress concentration at the edge of the window position and prevent the pad area from breaking.

[0022] Additional aspects and advantages of this invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0023] The above and / or additional aspects and advantages of this utility model will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:

[0024] Figure 1 This is a schematic diagram of the stacked structure of a flexible circuit board with a direct soldering structure according to an embodiment of the present invention.

[0025] Figure 2 This is one of the top view schematic diagrams of a flexible circuit board with a direct soldering structure according to an embodiment of the present utility model;

[0026] Figure 3 for Figure 2 The center circle shows a magnified view of a portion at position A;

[0027] Figure 4 This is a second top view schematic diagram of a flexible circuit board with a direct soldering structure according to an embodiment of the present utility model;

[0028] Figure 5 for Figure 4 The center circle shows a magnified view of position B.

[0029] Figure label:

[0030] Copper layer 100, main body 110, epitaxial part 120, pad area 121, first protective layer 200, first window position 210, wave structure 211, second protective layer 300, second window position 310. Detailed Implementation

[0031] The embodiments of this utility model are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this utility model, and should not be construed as limiting this utility model.

[0032] In the description of this utility model, it should be understood that the directional descriptions, such as up, down, front, back, left, right, etc., indicate the directional or positional relationship based on the directional or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0033] In the description of this utility model, "several" means one or more, "multiple" means two or more, "greater than," "less than," and "exceeding" are understood to exclude the stated number, while "above," "below," and "within" are understood to include the stated number. If "first," "second," etc., are used in the description, they are only for distinguishing technical features and should not be construed as indicating or implying relative importance, or implicitly indicating the number of indicated technical features, or implicitly indicating the sequential relationship of the indicated technical features.

[0034] In the description of this utility model, unless otherwise explicitly defined, the terms "setting", "installation", "connection", etc. should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this utility model in combination with the specific content of the technical solution.

[0035] Example 1

[0036] Please refer to Figure 1 This embodiment discloses a flexible circuit board with a direct-soldering structure, including a copper layer 100, a first protective layer 200, and a second protective layer 300. Please refer to... Figure 2 and Figure 3 The copper layer 100 has a main body 110 and an extended portion 120 connected integrally. Multiple extended portions 120 extend outward from the edge of the main body 110. Each extended portion 120 has a pad area 121 and is used to replace the original nickel sheet for soldering to the aluminum-palladium of the battery via the pad area 121. A first protective layer 200 covers the first surface of the copper layer 100 and has a first window position 210 adapted to the position of the pad area 121. A second protective layer 300 covers the second surface of the copper layer 100 and has a second window position 310 adapted to the position of the pad area 121. At least one edge of the second window position 310 and the first window position 210 are offset from each other on the projection of the copper layer 100 (e.g., ...). Figure 3 (The area marked L). Both the first protective layer 200 and the second protective layer 300 are PI films (polyimide films).

[0037] An extension portion 120 extending outward from the edge is provided in the main body portion 110 of the copper layer 100, and a pad area 121 is provided on the extension portion 120. The pad area 121 of the extension portion 120 can be directly welded to the aluminum palladium of the battery, which can eliminate the need for nickel sheets and avoid the welding quality problems of nickel sheets. The first protective layer 200 and the second protective layer 300 can provide physical support and surface protection for the copper layer 100. The first protective layer 200 and the second protective layer 300 are respectively provided with a first window position 210 and a second window position 310, which can expose the two opposite surfaces of the pad area 121, which facilitates ultrasonic welding of the pad area 121 to the aluminum palladium. The staggered edges of the first window position 210 and the second window position 310 can prevent stress concentration at the edges of the window positions, prevent the pad area 121 from breaking, and effectively improve the reliability of use. It is worth mentioning that, in this embodiment, the flexible circuit board has a structure of copper layer 100 + protective layer, and the protective layers on both the upper and lower surfaces of the pad area 121 are provided with corresponding openings to expose the pad area 121, making the pad area 121 a full copper structure, which meets the requirements of ultrasonic welding.

[0038] During ultrasonic welding, one of the first window position 210 and the second window position 310 contacts the aluminum palladium of the battery, while the other of the first window position 210 and the second window position 310 contacts the welding head of the ultrasonic welding equipment. Since the pad area 121 is an all-copper structure, to improve the connection reliability between the pad area 121 and the epitaxial portion 120, at least one edge of the second window position 310 and the first window position 210 is misaligned by a width of 0.5 ± 0.01 mm on the projection of the copper layer 100. Please refer to... Figure 3 , Figure 3 This is a top-down structural diagram, showing that the edges of the first window position 210 and the second window position 310 are misaligned on the projection of the copper layer 100, and the width of the misalignment is as shown. Figure 3 As indicated by the mark L, L = 0.5 ± 0.01 mm. Compared to the edge alignment of the first window position 210 and the second window position 310, the edge misalignment design of this embodiment can avoid the concentration of bending stress at the edge of the window position during use, effectively preventing the solder pad area 121 from breaking. In other application examples, the multiple edges of the first window position 210 and the second window position 310 can be misaligned to prevent bending stress from concentrating on different side edges, effectively preventing breakage in different directions.

[0039] Please refer to Figure 4 and Figure 5To further improve the reliability of the pad area 121, at least one edge of the second window position 310 and the first window position 210 is provided with a wave structure 211. For example, the edge of the first window position 210 is provided with a wave structure 211, while the edges of the second window position 310 are all straight structures; another example is that the edges of the first window position 210 are all conventional straight structures, while at least one edge of the second window position 310 is provided with a wave structure 211; yet another example is that the edges of both the first window position 210 and the second window position 310 are provided with wave structures 211, and the crests and troughs of the wave structures 211 are staggered; yet another example is that the edges of the second window position 310 and the first window position 210 that are staggered are provided with wave structures 211. The window edges of the wave structure 211 can prevent the bending stress generated in the pad area 121 during use from concentrating on the same straight line, thus preventing breakage.

[0040] The copper layer 100 has a thickness of 35 μm, the first protective layer 200 has a thickness of 60 μm, and the second protective layer 300 has a thickness of 50 μm. Both the first protective layer 200 and the second protective layer 300 are connected to the copper layer 100 using an adhesive. The total thickness of the flexible circuit board in this embodiment is approximately 160 μm, which is thin enough to meet the signal acquisition requirements of ultrasonic welding and use. The widths of the first window position 210 and the second window position 310 are both greater than the width of the pad area 121. For example, the left and right sides of the first window position 210 and the second window position 310 extend beyond the edge of the pad area 121 to fully expose the pad area 121.

[0041] Example 2

[0042] Please refer to Figure 1 This utility model embodiment provides a flexible circuit board with a direct-soldering structure, including a copper layer 100, a first protective layer 200, and a second protective layer 300, both of which are PI films (polyimide films). Please refer to... Figure 4 and Figure 5The copper layer 100 has a main body portion 110 and an extension portion 120 connected together. The extension portion 120 extends outward from the edge of the main body portion 110 and a pad area 121 is provided on the extension portion 120. A first protective layer 200 covers the first surface of the copper layer 100 and a first window position 210 is provided on the first protective layer 200 adapted to the position of the pad area 121. A second protective layer 300 covers the second surface of the copper layer 100 and a second window position 310 is provided on the second protective layer 300 adapted to the position of the pad area 121. At least one edge of the second window position 310 and the first window position 210 is provided with a wave structure 211. For example, the edges of the first window position 210 are all conventional straight lines, while at least one edge of the second window position 310 has a wavy structure 211; or, for example, the edges of the first window position 210 have a wavy structure 211, while the edges of the second window position 310 are all straight lines; or, for example, the edges of both the first window position 210 and the second window position 310 have wavy structures 211, and the crests and troughs of the wavy structures 211 are staggered; or, for example, the staggered edges of the second window position 310 and the first window position 210 have wavy structures 211. The window edges of the wavy structure 211 can prevent the bending stress generated in the pad area 121 during use from concentrating on the same straight line, thus preventing breakage.

[0043] An extension portion 120 extending outward from the edge is provided in the main body portion 110 of the copper layer 100, and a pad area 121 is provided on the extension portion 120. The pad area 121 of the extension portion 120 can be directly welded to the aluminum palladium of the battery, which can eliminate the need for nickel sheets and avoid the welding quality problems of nickel sheets. The first protective layer 200 and the second protective layer 300 can provide physical support and surface protection for the copper layer 100. The first protective layer 200 and the second protective layer 300 are respectively provided with a first window position 210 and a second window position 310, which can expose the two opposite surfaces of the pad area 121, which facilitates ultrasonic welding of the pad area 121 to the aluminum palladium. At least one edge of the first window position 210 and the second window position 310 is provided with a wave structure 211 to prevent stress concentration at the edge of the window position and prevent the pad area 121 from breaking.

[0044] The copper layer 100 has a thickness of 35 μm, the first protective layer 200 has a thickness of 60 μm, and the second protective layer 300 has a thickness of 50 μm. Both the first protective layer 200 and the second protective layer 300 are connected to the copper layer 100 using an adhesive. The total thickness of the flexible circuit board in this embodiment is approximately 160 μm, which is thin enough to meet the signal acquisition requirements of ultrasonic welding and use. The widths of the first window position 210 and the second window position 310 are both greater than the width of the pad area 121. For example, the left and right sides of the first window position 210 and the second window position 310 extend beyond the edge of the pad area 121 to fully expose the pad area 121.

[0045] Example 3

[0046] This embodiment provides an integrated busbar, including the flexible circuit board with a direct-welding structure of Embodiment 1 or Embodiment 2 described above. An extension portion 120 extending outward from the edge is provided on the main body portion 110 of the copper layer 100, and a pad area 121 is provided on the extension portion 120. Direct welding to the aluminum palladium of the battery can be achieved through the pad area 121 of the extension portion 120, eliminating the need for nickel sheets and avoiding welding quality issues associated with nickel sheets. The first protective layer 200 and the second protective layer 300 provide physical support and surface protection for the copper layer 100. The first protective layer 200 and the second protective layer 300 are respectively provided with a first window position 210 and a second window position 310, exposing the two opposing surfaces of the pad area 121, facilitating ultrasonic welding between the pad area 121 and the aluminum palladium. The staggered edges of the first window position 210 and the second window position 310, or the provision of a wave structure 211, prevent stress concentration at the edges of the window positions, preventing breakage of the pad area 121.

[0047] The embodiments of the present utility model have been described in detail above with reference to the accompanying drawings. However, the present utility model is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present utility model.

Claims

1. A flexible circuit board having a direct solder structure, characterized by, include: The copper layer (100) has a main body (110) and an epitaxial portion (120) connected together. The epitaxial portion (120) extends outward from the edge of the main body (110), and a pad area (121) is provided on the epitaxial portion (120). A first protective layer (200) covers the first surface of the copper layer (100), and the first protective layer (200) is adapted to the position of the pad area (121) to provide a first window position (210). A second protective layer (300) covers the second surface of the copper layer (100). The second protective layer (300) is provided with a second window position (310) adapted to the position of the pad area (121). At least one edge of the second window position (310) and the first window position (210) are offset from each other on the projection of the copper layer (100).

2. The flexible circuit board with straight solder structure according to claim 1, wherein, The width by which at least one edge of the second window position (310) and the first window position (210) is misaligned with each other on the projection of the copper layer (100) is 0.5±0.01mm.

3. The flexible circuit board having a direct bonding structure according to claim 1, wherein, At least one edge of the second window position (310) and the first window position (210) is provided with a wave structure (211).

4. The flexible circuit board having a direct bonding structure according to claim 3, wherein, The edges of the second window position (310) and the first window position (210) that are offset from each other are provided with a wave structure (211).

5. The flexible circuit board having a straight wire bonding structure according to any one of claims 1 to 4, wherein, The copper layer (100) has a thickness of 35 μm, the first protective layer (200) has a thickness of 60 μm, and the second protective layer (300) has a thickness of 50 μm.

6. The flexible circuit board having a straight wire bonding structure according to any one of claims 1 to 4, wherein The widths of the first window position (210) and the second window position (310) are both greater than the width of the pad area (121).

7. A flexible circuit board with a direct-soldering structure, characterized in that, include: The copper layer (100) has a main body (110) and an epitaxial portion (120) connected together. The epitaxial portion (120) extends outward from the edge of the main body (110), and a pad area (121) is provided on the epitaxial portion (120). A first protective layer (200) covers the first surface of the copper layer (100), and the first protective layer (200) is adapted to the position of the pad area (121) to provide a first window position (210). A second protective layer (300) is provided on the second surface of the copper layer (100). The second protective layer (300) is adapted to the position of the pad area (121) and a second window position (310) is provided. At least one edge of the second window position (310) and the first window position (210) is provided with a wave structure (211).

8. The flexible circuit board having a direct bonding structure according to claim 7, wherein, The copper layer (100) has a thickness of 35 μm, the first protective layer (200) has a thickness of 60 μm, and the second protective layer (300) has a thickness of 50 μm.

9. The flexible circuit board with straight solder structure according to claim 7 or 8, wherein, The widths of the first window position (210) and the second window position (310) are both greater than the width of the pad area (121).

10. An integrated busbar, characterized by, Including the flexible circuit board with a direct-soldering structure as described in any one of claims 1 to 9.

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