Signal acquisition assembly applied to battery connection system and connection process of signal acquisition assembly

Abstract

The invention discloses a signal acquisition assembly applied to a battery connection system and a connection process of the signal acquisition assembly. The signal acquisition assembly comprises an acquisition main body and an acquisition branch, and the connection process comprises the following steps: preprocessing the connection position of the acquisition main body and the acquisition branch so that there is no gap between the connection position of the acquisition main body and the acquisition branch, and then performing laser welding on the connection position of the acquisition branch so that the acquisition main body and the acquisition branch are reliably connected into a whole. Firstly, the connecting position of the collecting body and the collecting branch is preprocessed to eliminate the gap between the collecting body and the collecting branch, the problem that welding penetration or hole blasting is prone to occurring during laser welding due to the fact that a thin material non-brazing-filler-metal laser welding gap cannot be eliminated is solved, laser welding is adopted after the gap is eliminated, direct laser welding of the collecting branch and the collecting body is achieved, and welding efficiency is improved. The method is simple, and a new processing technology reference is provided for realizing the connection of the acquisition main body and the acquisition branch in the industry.

Description

Technical Field

[0001] The present invention relates to the field of battery connection systems, and particularly to a signal acquisition component applied to a battery connection system and its connection process. Background Art

[0002] The battery connection system mainly consists of a battery connection and a signal acquisition system. The battery signal acquisition system mainly includes an acquisition main body (such as an FFC) and a signal acquisition branch (such as an FPC or an FDC), which are connected together.

[0003] In the existing traditional battery connection system 10', the connection between the acquisition branch 12' and the acquisition main body 11' usually adopts a laser soldering process. The laser soldering process is borrowed from the SMT process of the FPC and has mature equipment and manufacturing processes. Currently, the industry uses this process. However, when this process is used for signal acquisition components, there are many disadvantages, specifically as follows: 1. The FDC signal acquisition sheet is relatively thin, and the wires of the FFC body are relatively thin. Both are prone to bending and deformation. There is a problem of instability in the gap 14' between the FDC and the FFC during laser soldering. When the gap 14' is too large, the solder 13' cannot fill the entire gap 14' (as Figure 1 ) or when the gap is too small, there is relatively too much solder, which overflows to other places, resulting in abnormal welding; 2. The welding heat conducts quickly, and the welding heating time is long. Each welding takes 3 - 4S; 3. After welding, only 3D AOI inspection can be performed. The FDC acquisition branch covers most of the soldering positions, making inspection difficult; 4. There are many processes in the wire body, and the costs of processes such as dot soldering, SPI, laser soldering, and 3D AOI are high; 5. The FFC wires need to be tin-plated, further increasing the cost; 6. The FDC needs to open micro-holes for 3D AOI inspection, increasing the production cost.

[0004] Due to the many disadvantages of laser soldering, the demand for solderless laser welding technology is increasing day by day. It has the following advantages: 1. The welding energy is stable and there is no attenuation during long-term use; 2. There is no material loss, no auxiliary materials are required, and no consumables are required; 3. It is fast, usually dozens of milliseconds; 4. The position control is accurate, especially suitable for local area welding of thin wires. However, it also has disadvantages. For example, the two objects to be welded need to be closely fitted. Especially for very thin materials, low energy is required and the fit needs to be extremely tight. The FFC main body and the FDC branch need to be welded with zero gap. Currently, two main solutions are adopted, but the applicant found that both of these solutions have certain defects. One is to use two pressing plates or blocks 16' to press tightly on both sides of the welding positions of the FFC main body and the FDC branch relatively and at intervals, and then perform laser welding. In this solution, a reliable zero gap cannot be achieved in the welding area (as Figure 3As shown, there is still a relatively smaller gap 14', that is, the gap 14' is not eliminated). Second, a glass plate is used to press the FFC main body and the FDC branch (such as Figure 4 ), and the laser passes through the glass plate 17' for welding. Although zero gap can be ensured, due to the problem of solder 15' splashing (such as Figure 2 shown), the glass plate will be contaminated and cannot be used for a long time, and the service life of the glass plate is extremely short. Due to the above problems, solderless laser welding cannot be achieved in the current industry. Therefore, in order to solve the above problems, the present invention comes into being. Summary of the Invention

[0005] In view of at least one of the above-mentioned existing technical problems, the object of the present invention is to provide a signal acquisition component applied to a battery connection system and its connection process.

[0006] The technical solution of the present invention is as follows: An object of the present invention is to provide a connection process for a signal acquisition component applied to a battery connection system. The signal acquisition component includes an acquisition main body and an acquisition branch connected to the acquisition main body. The connection process includes first preprocessing the connection positions of the acquisition main body and the acquisition branch so that there is no gap between the connection positions of the two, and then performing laser welding at the connection positions so that the two connection positions are effectively connected.

[0007] Preferably, the preprocessing includes ultrasonic preprocessing, embossing preprocessing or pressing preprocessing.

[0008] Preferably, the purpose of the preprocessing is to eliminate the welding gap. During subsequent laser welding, there is no gap and no peeling between the two. The preprocessing has a relatively low requirement for the connection strength. After the preprocessing, the peeling strength at the connection between the acquisition main body and the acquisition branch is not greater than 2N.

[0009] Preferably, the preprocessing is ultrasonic preprocessing or embossing preprocessing, and a strip-shaped or block-shaped preprocessing part is formed at the connection position of the acquisition main body and the acquisition branch after the preprocessing; After the laser welding, a plurality of laser welding parts are formed, and the sum of the areas of all the laser welding parts is not greater than the area of the preprocessing part.

[0010] Preferably, the laser welding parts are welding points or welding lines; When the laser welding parts are welding points, a plurality of the welding points are spaced apart along the length direction of the strip-shaped or block-shaped preprocessing part; When the laser welding part is a welding line, a plurality of the welding lines are spaced apart along the length or width direction of the strip-shaped or block-shaped pretreatment part, and any one of the welding lines extends along the width or length direction of the strip-shaped or block-shaped pretreatment part, or a plurality of the welding lines are arranged in a loop shape.

[0011] Preferably, the peel strength at the joint after laser welding is not less than 8 N.

[0012] Preferably, the acquisition main body is an FPC, an FFC or an FDC, and the acquisition branch is an FPC, an FFC or an FDC.

[0013] Another object of the present invention is to provide a signal acquisition component processed by using the above connection process.

[0014] Compared with the prior art, the advantages of the present invention are: The present invention is applied to a signal acquisition component and its connection process in a battery connection system. First, the connection position between the acquisition main body and the acquisition branch is pretreated to eliminate the gap between the two, solving the problem that the gap cannot be eliminated in laser welding without solder for thin materials, which easily causes welding through or explosion holes during welding. After eliminating the gap, laser welding is used to achieve direct laser welding of the acquisition branch and the acquisition main body. The method is simple and provides a new processing technology reference for the industry to realize the connection of the acquisition main body and the acquisition branch. Description of the Drawings

[0015] The present invention will be further described below in conjunction with the drawings and embodiments: Figure 1 It is a schematic structural diagram of a signal acquisition component using an existing laser soldering process and a partial enlarged view of part A; Figure 2 It is a schematic diagram of an existing structure where a glass plate presses an FFC main body and an FDC branch and laser passes through the glass plate for welding, resulting in solder spattering, and a partial enlarged view of part B; Figure 3 It is a schematic structural diagram of a signal acquisition component using an existing laser soldering process after eliminating the gap with a pressing plate or a pressing block and a partial enlarged view of part C; Figure 4 It is a schematic structural diagram of an existing structure where a glass plate presses an FFC main body and an FDC branch to eliminate the gap and then uses laser welding, and a partial enlarged view of part D; Figure 5 It is a schematic structural diagram of a signal acquisition component processed by using the connection process of the embodiment of the present invention before pretreatment and a partial enlarged view of part E; Figure 6 It is a schematic structural diagram of a signal acquisition component processed by using the connection process of the embodiment of the present invention during pretreatment and a partial enlarged view of part F; Figure 7 A schematic diagram of a structure of a signal acquisition component processed by the connection process of the embodiment of the present invention, which is laser welded after ultrasonic pretreatment or embossing pretreatment (the laser welding part is a welding point); Figure 8 is Figure 7 A partial enlarged view of part G in; Figure 9 Another schematic diagram of a structure of a signal acquisition component processed by the connection process of the embodiment of the present invention, which is laser welded after ultrasonic pretreatment or embossing pretreatment (the laser welding part is a welding line); Figure 10 is Figure 9 A partial enlarged view of part H in; Figure 11 One of the schematic diagrams of a structure of a signal acquisition component processed by the connection process of the embodiment of the present invention, which is laser welded after press-fitting pretreatment (the laser welding part is a welding point).

[0016] Wherein: 10, signal acquisition component; 11, acquisition main body; 12, acquisition branch; 13, gap; 14, pretreatment part; 15, laser welding part. Specific embodiments

[0017] To make the objectives, technical solutions and advantages of the present invention clearer and more understandable, the present invention will be further described in detail below in conjunction with specific embodiments and with reference to the accompanying drawings. It should be understood that these descriptions are only exemplary and are not intended to limit the scope of the present invention. In addition, in the following description, the descriptions of well-known structures and technologies are omitted to avoid unnecessarily confusing the concepts of the present invention. Embodiment 1

[0018] The embodiment of the present invention provides a connection process for a signal acquisition component applied to a battery connection system. Refer to Figures 5 to 11 , wherein, the signal acquisition component 10 mainly includes an acquisition main body 11 and an acquisition branch 12. The acquisition main body 11 has many metal lines such as copper wires. For the acquisition main body 11, it can be selected as the existing conventional FPC (Flexible Printed Circuit, flexible printed circuit board), FFC (Flexible Flat Cable, flexible flat cable) or FDC (Flexible Die-cutting Circuit, flexible die-cut circuit board). The signal acquisition branch 12 is usually connected to the acquisition main body 11 and a temperature sensing device, etc., to realize the signal connection between the temperature sensing device and the acquisition main body 11. For the acquisition branch 12, it can be selected as the existing conventional FPC, FFC or FDC. In an example of the embodiment of the present invention, the acquisition main body 11 is an FFC and the acquisition branch 12 is an FDC.

[0019] Since the thicknesses of both the collection main body 11 and the collection branch 12 are very thin, usually only about dozens to one hundred micrometers, in order to achieve solderless laser welding of the two, it is necessary to ensure that there is no gap between the connection positions of the two during laser welding (as Figure 5 shown, before preprocessing, there is a gap 13 between the connection positions or at the connection of the collection main body 11 and the collection branch 12). To achieve this purpose, in the embodiments of the present invention, first, the connection positions of the collection main body 11 and the collection branch 12 are preprocessed. The purpose of the preprocessing is to eliminate the gap 13 between the connection positions or at the connection of the collection main body 11 and the collection branch 12, so that the connection positions or the connection of the collection main body 11 and the collection branch 12 are closely attached together (see Figure 6 , after preprocessing, there is no gap between the connection positions or at the connection of the collection main body 11 and the collection branch 12), so as to facilitate subsequent direct laser welding, solve the quality risks such as welding through or welding holes that may occur during subsequent laser welding, and achieve direct laser welding of the collection main body 11 and the collection branch 12. After the gap 13 at the connection position of the collection main body 11 and the collection branch 12 is eliminated by preprocessing, then laser welding is adopted, so that an effective connection is achieved between the two connection positions. The purpose of this step is to connect the collection main body 11 and the collection branch 12 into one body.

[0020] For the preprocessing, it is different from the methods of pressing with a pressing plate and pressing with a glass plate in the background art. Specifically, see Figures 6 to 11 , in this embodiment, the preprocessing method can be selected from ultrasonic preprocessing, embossing preprocessing or pressing preprocessing.

[0021] Specifically, for ultrasonic preprocessing, the main purpose of ultrasonic preprocessing in the embodiments of the present invention is not to connect the collection main body 11 and the collection branch 12, but to eliminate the gap 13 at the connection position between the two as Figure 5 shown. This is different from the purpose of directly connecting two parts to be welded together by ultrasonic waves in the prior art. Although ultrasonic preprocessing will cause a connection between the two, the connection strength or peel strength of ultrasonic preprocessing in this embodiment is essentially different from the connection strength or peel strength required for ultrasonic welding in the prior art, and there is an order-of-magnitude difference. In the embodiments of the present invention, the peel strength of the connection position of the collection main body 11 and the collection branch 12 after ultrasonic preprocessing is not greater than 2 N, such as 0.5 N, 1 N, 1.5 N, 2 N, etc. Specific technical parameters for ultrasonic preprocessing are not specifically described and limited, and those skilled in the art can obtain them by adjustment.

[0022] As Figures 7 to 10As shown, in the embodiment of the present invention, a pretreatment part 14 is formed at the connection position between the acquisition main body 11 and the acquisition branch 12 after ultrasonic pretreatment. Regarding the shape of the pretreatment part 14, for example, Figures 7 to 10 As shown, in the embodiment of the present invention, it is exemplarily strip-shaped or block-shaped. The connection position on the acquisition main body 11 is one of the flat square metal wires, and the pretreatment part 14 is a square formed on the acquisition branch 12 and matching the flat metal wire. It should be noted that the area of the pretreatment part 14 is not less than the area of the metal wire, that is, the connection position of the acquisition main body 11. It can be obviously known that here it refers to that the width of the pretreatment part 14 is not less than the width of the metal wire but the length is less than the length of the metal wire. Correspondingly, a number of laser welding parts 15 are formed by laser welding. Specifically, laser welding is performed on the side of the connection position of the acquisition branch 12 facing away from the acquisition main body 11, that is, the laser welding part 15 is formed on the side of the acquisition branch 12 facing away from the acquisition main body 11. Regarding the shape of the laser welding part 15, an exemplary one is, for example, Figure 7 and Figure 8 As shown, the laser welding part 15 in this embodiment is a welding point. As an alternative embodiment, for example, Figure 9 and Figure 10 As shown, the laser welding part 15 can also be a welding line. When the laser welding part 15 is a welding point, a laser spot welder can be used for spot welding operations. Exemplarily, laser spot welding can be performed at intervals along the length direction of the pretreatment part 14 to form a plurality of spaced-apart substantially circular welding points on the pretreatment part 14 (as shown in Figure 7 and Figure 8 ), and the number of welding points is not specifically described and limited. When the laser welding part 15 is a welding line, it can be as shown in Figure 9 and Figure 10 As shown, it consists of several arranged at intervals along the width direction of the pretreatment part 14 and any welding line extends along the length direction of the pretreatment part 14. The number of welding lines is also not described and limited, Figure 10Exemplarily, there are three welding lines; of course, it can also be a plurality of welding lines arranged at intervals along the length direction of the pretreatment part 14, and any welding line extends along the width direction of the pretreatment part 14; it can also be, for example, a welding line arranged in a figure-eight shape (not shown), such as two or more concentrically spaced square or circular or triangular or other geometric-shaped welding circles, or it can be one or more continuous welding lines wound from the inside out or from the outside in, etc. While maintaining the welding strength, the aesthetics can also be improved. As for the effective connection mentioned above, it is defined by the peel strength at the connection position. In the embodiment of the present invention, after pretreatment and then laser welding, the peel strength at the connection position between the acquisition main body 11 and the acquisition branch 12 of the signal acquisition component 10 is not less than 8 N, such as 8 N, 9 N, 10 N, 15 M, 20 N, etc., achieving an effective connection. The technical parameters of the laser welding in this step are not specifically described and limited, and those skilled in the art can achieve it by adjustment.

[0023] For the embossing pretreatment, it is an existing conventional embossing technique. By pressing the connection position between the acquisition main body 11 and the acquisition branch 12 with an embossing die with concavities and convexities, the gap between the two can be effectively eliminated, and the connection between the two can also be achieved to realize the direct laser welding of the acquisition main body 11 and the acquisition branch 12. When embossing pretreatment is adopted, Figures 7 to 10 the pretreatment part 14 in it is an embossed pattern that fits together with concavities and convexities.

[0024] For the pressing pretreatment, it can be a pressing treatment technique well-known to those skilled in the art in the existing technology, such as pressing the two together tightly with a pressing die, and specific descriptions and limitations are not made here. As Figure 9 shown, after the pressing pretreatment, there is no obvious pretreatment part formed at the connection position or the connection of the acquisition main body 11 and the acquisition branch 12 like the ultrasonic pretreatment or the embossing pretreatment. Since both the acquisition main body 11 and the acquisition branch 12 are made of metal, due to the existence of stress during pressing, the gap may rebound during subsequent laser welding, resulting in an effect that is not as good as the ultrasonic pretreatment or the embossing pretreatment. However, it can be solved by controlling the pressure and time during pressing, and specific descriptions and limitations are not made. Those skilled in the art can adjust according to actual needs. For the laser welding part 15, Figure 11 exemplarily, there are a plurality of welding points arranged at intervals along the length direction of the wire of the acquisition main body 11.

[0025] For the connection process of the signal acquisition component in this embodiment, the connection positions of the acquisition main body 11 and the acquisition branch 12 are pre-treated first to eliminate the gap between the two, solving the problem that the gap in laser soldering without filler metal cannot be eliminated and the problem that when the thickness of the material to be welded is very thin, such as about ten to one hundred micrometers, it is easy to burn through or burst holes during laser welding. After eliminating the gap, laser welding is used, realizing the direct laser welding of the acquisition branch 12 and the acquisition main body 11. The method is simple and provides a new processing technology reference for the industry to connect the acquisition main body and the acquisition branch. Embodiment 2

[0026] The embodiment of the present invention provides a signal acquisition component 10. The structural composition of the signal acquisition component 10 in this embodiment is the same as that of the existing conventional signal acquisition component 10. The only difference lies in the connection process of the acquisition main body 11 and the acquisition branch 12. The connection process of the acquisition main body 11 and the acquisition branch 12 in the signal acquisition component 10 in this embodiment adopts the connection process of Embodiment 1. Therefore, it has at least the beneficial effects of Embodiment 1, which will not be elaborated here.

[0027] It should be understood that the above specific embodiments of the present invention are only used for exemplary illustration or explanation of the principle of the present invention, and do not constitute a limitation to the present invention. Therefore, any modifications, equivalent replacements, improvements, etc. made without departing from the spirit and scope of the present invention shall be included within the protection scope of the present invention. In addition, the appended claims of the present invention are intended to cover all changes and modifications that fall within the scope and boundaries of the appended claims, or equivalent forms of such scope and boundaries.

Claims

1. A connection process for a signal acquisition component applied to a battery connection system, the signal acquisition component comprising an acquisition main body and an acquisition branch connected to the acquisition main body, characterized in that, The described connection process includes first preprocessing the connection positions of the collection main body and the collection branch so that there is no gap between the connection positions of the two, and then performing laser welding at the connection positions so that the two connection positions are effectively connected.

2. The connection process according to claim 1, wherein, The described preprocessing includes ultrasonic preprocessing, embossing preprocessing, or pressing preprocessing.

3. The connection process according to claim 2, characterized in that, After the preprocessing is completed, the peel strength at the connection of the collection main body and the collection branch is not greater than 2 N.

4. The connection process according to claim 2, wherein The preprocessing is ultrasonic preprocessing or embossing preprocessing, and a strip-shaped or block-shaped preprocessing part is formed at the connection position of the collection main body and the collection branch after the preprocessing; After the laser welding, several laser welding parts are formed, and the sum of the areas of all the laser welding parts is not greater than the area of the preprocessing part.

5. The joining process according to claim 4, characterized in that, The laser welding parts are welding points or welding lines; When the laser welding parts are welding points, several of the welding points are spaced apart along the length direction of the strip-shaped or block-shaped preprocessing part; When the laser welding parts are welding lines, several of the welding lines are spaced apart along the length or width direction of the strip-shaped or block-shaped preprocessing part, and any one of the welding lines extends along the width or length direction of the strip-shaped or block-shaped preprocessing part, or several of the welding lines are arranged in a zigzag pattern.

6. The connection process according to claim 1, characterized in that The peel strength at the connection after laser welding is not less than 8 N.

7. The connection process according to claim 1, characterized in that, The collection main body is an FPC, FFC, or FDC, and the collection branch is an FPC, FFC, or FDC.

8. A signal acquisition component, characterized in that, It is processed by using the connection process according to any one of claims 1-7.

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