A connection structure between a circuit board and a battery and a battery pack

Abstract

The invention relates to a connection structure between a circuit board and a battery and a battery pack, wherein: the connection structure between the circuit board and the battery comprises a circuit board and a battery assembly, a nickel sheet is provided on the battery assembly, a pin is provided on the nickel sheet, a connecting sheet is provided at the bottom end of the circuit board, an elastic clamp is provided on the battery assembly, the connecting sheet and the pin are fixedly connected by laser welding, and a through hole is provided on the circuit board. The advantages of the invention are: by providing a connecting sheet that fits the pin on the circuit board, and laser welding is adopted to fix the connecting sheet and the pin, since the connecting sheet is provided at the bottom end of the circuit board, it is not necessary to process a through hole for the pin to pass through on the circuit board, so that when the nickel sheet and the battery are spot-welded, it is not necessary to install the circuit board on the battery assembly, and the nickel sheet spot welding and the circuit board installation are two independent processes, thereby reducing the damage to the circuit board during the nickel sheet spot welding and improving the service life of the circuit board.

Description

Technical Field

[0001] The invention relates to a connection structure between a circuit board and a battery and a battery pack. Background Art

[0002] Cordless power tools and other cordless devices use rechargeable battery packs as a power source. These battery packs are often removably connected to other tools or devices. The battery packs can be repeatedly charged and discharged to allow the user to reuse the tool without having to purchase a new power source.

[0003] With the continuous development of battery packs, the connection structure between circuit boards and battery components is becoming more and more important. For example, Chinese patent application number 2023233651493 discloses a connection structure between a circuit board and a connector and a battery pack. Specifically, the pins of the connector pass through the vias of the circuit board and are connected to the pads by soldering. The above connection structure has the following defects: when installing the circuit board, the vias need to be aligned with the pins, and the installation accuracy is high. In addition, the soldering connection structure requires a high level of operation from the operator. Improper operation may lead to poor welding quality, such as the inability of tin to fill the seams, pores and cracks, which may lead to short circuits, cold solder joints and cracks in the solder joints, thereby affecting the performance of the circuit board. In addition, there are environmental pollution and health hazards during the soldering operation, which is not conducive to long-term operation. In addition, when the connector and the battery are spot-welded, the circuit board needs to be installed on the battery rack, which may easily cause damage to the circuit board during spot welding, greatly affecting the service life of the circuit board. Summary of the invention

[0004] The purpose of the present invention is to solve the problem that when the existing circuit board and the battery are connected by soldering, the circuit board needs to be installed on the battery rack first, thereby causing damage to the circuit board. A connection structure between the circuit board and the battery is proposed. By arranging a connecting piece that fits with the pins at the bottom of the circuit board, there is no need to process through holes on the circuit board for the pins to pass through. When the nickel sheet is spot welded, the circuit board does not need to be installed on the battery assembly. The nickel sheet spot welding and the circuit board installation are two independent processes, thereby reducing the damage to the circuit board during the nickel sheet spot welding and improving the service life of the circuit board.

[0005] In order to solve the above technical problems, the present invention is implemented through the following technical solutions: a connection structure between a circuit board and a battery, comprising a circuit board and a battery assembly, the battery assembly is provided with a nickel sheet, the nickel sheet is provided with a pin, the bottom end of the circuit board is provided with a connecting sheet that fits with the pin, the battery assembly is provided with an elastic clip, when the circuit board is inserted into the elastic clip, the connecting sheet fits with the pin, the connecting sheet and the pin are fixedly connected by laser welding, and the circuit board is provided with a through hole for facilitating laser welding of the connecting sheet and the pin.

[0006] Preferably, the penetration hole is a connection groove, and the connection groove is arranged on the side wall of the circuit board; or, the penetration hole is a strip hole, and the strip hole is arranged on the circuit board.

[0007] Preferably, the length of the through hole is L1, and the length of the pin is L2, wherein: 1.3L2≤ L1≤1.4L2.

[0008] Preferably, a positioning groove adapted to the connecting piece is provided on the circuit board.

[0009] Preferably, the connecting piece is a copper-tin alloy connecting piece or a nickel-plated steel strip connecting piece or a nickel connecting piece, and the thickness of the connecting piece is equal to the thickness of the pin.

[0010] Preferably, a positioning structure is provided between the battery assembly and the circuit board, and the positioning structure comprises positioning columns and positioning holes connected to each other.

[0011] Preferably, the positioning column is arranged on the battery assembly, and the positioning column is arranged in a vertical direction or a horizontal direction, the positioning hole is arranged on the circuit board, and the top end of the positioning column is provided with an arc chamfer.

[0012] Preferably, the elastic clamp comprises a locking block and a spring sheet, the locking block is fixedly connected to the battery assembly via the spring sheet, and the locking block is provided with an inclination angle.

[0013] Preferably, a short-circuit protection nickel sheet is provided between the circuit board and the battery assembly, and an opening corresponding to the short-circuit protection nickel sheet is provided on the circuit board.

[0014] In addition, the present invention also provides a battery pack, including a shell and a connection structure between a circuit board and a battery arranged in the shell, wherein the connection structure between the circuit board and the battery adopts the connection structure between the circuit board and the battery described above.

[0015] In summary, the advantages of the present invention are as follows: a connecting piece that fits the pin is provided on the circuit board, and the connecting piece and the pin are fixed by laser welding. Since the connecting piece is provided at the bottom end of the circuit board, there is no need to process a through hole for the pin to pass through on the circuit board, so that when the nickel sheet is spot-welded to the battery, there is no need to install the circuit board on the battery assembly. The nickel sheet spot welding and the circuit board installation are two independent processes, thereby reducing the damage to the circuit board during the spot welding of the nickel sheet and improving the service life of the circuit board. Not only the installation process of the circuit board is simplified, but also the installation structure of the pin is simplified, the contact area between the pin and the connecting piece is greatly increased, and the connecting piece can also be protected to a certain extent. Secondly, the fixed connection between the connecting piece and the pin is achieved by laser welding. Since laser welding has the advantages of fast speed, high efficiency and good quality, it can achieve rapid connection between the connecting piece and the pin, and can also improve the connection The welding quality of the connecting piece and the pin avoids the melting of tin and desoldering in a high temperature environment, which greatly improves the performance of the circuit board. The weld is flat and smooth, without pores and cracks, and has a good appearance. The welding stress and deformation are small during welding, which further improves the connection quality of the connecting piece and the pin. The setting of the elastic clamp can realize the rapid clamping of the circuit board on the battery assembly, avoid the movement of the circuit board during welding, and improve the welding efficiency. On the other hand, because the connecting piece fits on the pin when the circuit board is clamped into the elastic clamp, there will be no gap between the connecting piece and the pin, which further improves the quality of the weld. The weld can be set in different shapes according to actual needs to meet different welding needs. Finally, a through hole is set on the circuit board to facilitate the passage of the laser beam, so that the circuit board will not form a spatial interference with the laser welding, and the rapid welding and fixation of the connecting piece and the pin is realized. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The present invention will be further described below in conjunction with the accompanying drawings: Figure 1 A schematic structural diagram of a connection structure between a circuit board and a battery according to the present invention; Figure 2 It is a schematic diagram of the structure of the circuit board in the present invention; Figure 3 This is a schematic diagram of the structure of welding the circuit board and the nickel sheet in the present invention; Figure 4 It is a schematic diagram of the structure of the battery assembly in the present invention.

[0017] Reference numerals: 1 circuit board, 11 connecting piece, 12 through hole, 13 positioning groove, 14 opening, 2 battery assembly, 21 elastic card, 22 locking block, 23 spring piece, 24 inclination, 3 nickel sheet, 31 pin, 4 positioning structure, 41 positioning column, 42 positioning hole, 43 arc chamfer, 5 short circuit protection nickel sheet. DETAILED DESCRIPTION Embodiment 1

[0018] like Figure 1 , Figure 2 , Figure 3 and Figure 4 As shown, a connection structure between a circuit board and a battery comprises a circuit board 1 and a battery assembly 2, wherein a nickel sheet 3 is provided on the battery assembly 2, a pin 31 is provided on the nickel sheet 3, a connecting sheet 11 which fits with the pin 31 is provided at the bottom end of the circuit board 1, and an elastic clamp 21 is provided on the battery assembly 2. When the circuit board 1 is clamped into the elastic clamp 21, the connecting sheet 11 fits with the pin 31, and the connecting sheet 11 and the pin 31 are fixedly connected by laser welding. A through hole 12 is provided on the circuit board 1 for facilitating laser welding of the connecting sheet 11 and the pin 31. During installation, the connecting sheet is firstly welded to the circuit board by wave soldering, and the solder joints should be firm and reliable during welding, and the phenomenon of cold soldering and desoldering should not occur. Then, the nickel sheet is spot welded to the battery assembly, and the welded circuit board is installed on the battery assembly, and is installed on the battery assembly by the elastic clamp. Then, laser welding is used to realize the fixed connection between the connecting sheet and the pin, which simplifies the installation process of the circuit board.

[0019] By providing a connecting piece that fits the pin on the circuit board, and fixing the connecting piece and the pin by laser welding, since the connecting piece is provided at the bottom end of the circuit board, there is no need to process a through hole for the pin to pass through on the circuit board, so that when the nickel sheet is spot-welded to the battery, there is no need to install the circuit board on the battery assembly. The nickel sheet spot welding and the circuit board installation are two independent processes, thereby reducing the damage to the circuit board during the nickel sheet spot welding and improving the service life of the circuit board. Not only does it simplify the installation process of the circuit board, but it also simplifies the installation structure of the pin, greatly improves the contact area between the pin and the connecting piece, and can also provide a certain protection for the connecting piece. Secondly, the fixed connection between the connecting piece and the pin is achieved by laser welding. Since laser welding has the advantages of fast speed, high efficiency and good quality, it can achieve rapid connection between the connecting piece and the pin, and can also improve the connection between the connecting piece and the pin. The welding quality is improved, and the melting and desoldering of the weld in a high temperature environment are avoided, which greatly improves the performance of the circuit board. The weld is flat and smooth, without pores and cracks, and has a good appearance. The welding stress and deformation are small during welding, which further improves the connection quality of the connecting piece and the pin. The setting of the elastic clamp can realize the rapid clamping of the circuit board on the battery assembly, avoids the movement of the circuit board during welding, and improves the welding efficiency. On the other hand, when the circuit board is clamped into the elastic clamp, the connecting piece fits on the pin, so there will be no gap between the connecting piece and the pin, which further improves the quality of the weld. In addition, the weld can be set in different shapes according to actual needs to meet different welding needs. Finally, a through hole is set on the circuit board to facilitate the passage of the laser beam, so that the circuit board will not form a spatial interference with the laser welding, and the rapid welding and fixation of the connecting piece and the pin is realized.

[0020] The through hole 12 is a connection groove, and the connection groove is arranged on the side wall of the circuit board 1; or, the through hole 12 is a strip hole, and the strip hole is arranged on the circuit board 1. The present embodiment preferably adopts the structure of the connection groove. On the one hand, the circuit board will not form spatial interference with the laser beam during laser welding, which greatly improves the laser quality, and on the other hand, it will not reduce the installation strength of the circuit board. Specifically, the length of the through hole 12 is L1, and the length of the pin 31 is L2, where: 1.3L2≤ L1≤1.4L2. Through the setting of the above structure, on the one hand, the welding length of the weld can be increased, and the heat during welding can be dissipated in time without damaging the circuit board. In addition, the installation strength of the circuit board can be guaranteed and thermal deformation will not occur during welding. When L1<1.3L2, the heat cannot be dissipated. When L1>1.4L2, the installation strength of the circuit board is reduced, thereby reducing the service life of the circuit board.

[0021] The circuit board 1 is provided with a positioning groove 13 adapted to the connecting piece 11, which is conducive to the accurate positioning and installation of the connecting piece on the circuit board. The connecting piece in this embodiment is soldered in the positioning groove by wave soldering. The connecting piece should be firmly soldered on the circuit board and no false soldering or desoldering phenomenon should occur. The connecting piece 11 is a copper-tin alloy connecting piece or a nickel-plated steel strip connecting piece or a nickel connecting piece, and the thickness of the connecting piece is equal to the thickness of the pin 31. The connecting piece can also be set to other alloy parts. In this embodiment, the thickness of the pin is 0.25mm. The connecting piece is preferably a copper-tin alloy connecting piece. Since the copper-tin alloy connecting piece has good electrical conductivity, corrosion resistance and mechanical strength, it can not only improve the welding quality between the pin and the connecting piece, but also provide reliable current transmission, and can also keep good performance in a humid or corrosive environment. Secondly, setting the thickness of the connecting piece and the thickness of the pin to be equal is conducive to the continuity of the weld, can improve the welding quality of the connecting piece and the pin, will not affect the speed of laser welding, and can meet different welding temperatures. In addition, the copper-tin alloy connecting piece is easy to stamp.

[0022] A positioning structure 4 is provided between the battery assembly 2 and the circuit board 1. The positioning structure 4 includes mutually connected positioning posts 41 and positioning holes 42. The setting of the positioning structure can realize the positioning and installation of the circuit board. The positioning structure is set as a structure of mutually connected positioning posts and positioning holes. On the one hand, the positioning posts and the positioning holes are easy to process, which reduces errors in the processing process and improves the positioning accuracy. On the other hand, the positioning posts and the positioning holes make the installation and disassembly of the circuit board more convenient. The circuit board can be installed by simply aligning the positioning holes with the positioning posts, thereby improving the installation efficiency of the circuit board. Specifically, the positioning column 41 is arranged on the battery assembly 2, and the positioning column 41 is arranged in the vertical direction or the horizontal direction, the positioning hole 42 is arranged on the circuit board 1, and the top of the positioning column 41 is provided with an arc chamfer 43. The positioning column is arranged on the battery assembly and the positioning hole is arranged on the circuit board, which is beneficial to the installation and disassembly of the circuit board. Secondly, the positioning column is arranged in the vertical direction or the horizontal direction, and the structure of the positioning column can be set according to different installation requirements. In this embodiment, the positioning column is arranged on the bracket of the battery assembly, and the mounting structure of the positioning column and the bracket preferably adopts an integrated structure, which can simplify the mounting structure of the positioning column and the bracket, and can also improve the connection strength between the positioning column and the bracket. Finally, the setting of the arc chamfer makes the top edge of the positioning column smoother, which is convenient for the positioning column to be inserted into the positioning hole, reduces the stress concentration at the top of the positioning column, and improves the service life of the positioning column.

[0023] The elastic clamp 21 includes a locking block 22 and a spring 23. The locking block 22 is fixedly connected to the battery assembly 2 through the spring 23. The locking block 22 is provided with an inclination angle 24, and the elastic clamp is configured as a locking block and spring structure. Since the locking block is provided with an inclination angle, during installation, when the edge of the circuit board contacts the inclination angle, the locking block opens outward under the action of the spring, and the circuit board can be installed on the battery assembly. When the connecting piece fits with the pin, the locking block is reset under the reset action of the spring. At this time, the upper end surface of the circuit board is subjected to the force of the locking block, and the circuit board cannot shake in the vertical direction. In addition, the setting of the inclination angle is conducive to the installation positioning and disassembly of the locking block, reduces the force during installation positioning, and can achieve quick installation.

[0024] A short-circuit protection nickel sheet is provided between the circuit board 1 and the battery assembly 2, and an opening 14 corresponding to the short-circuit protection nickel sheet is provided on the circuit board 1. The short-circuit protection nickel sheet can protect the circuit board when a short circuit occurs, and the opening can realize the installation and fixation of the short-circuit protection nickel sheet. Embodiment 2

[0025] This embodiment also provides a battery pack, including a shell and a connection structure between a circuit board and a battery arranged in the shell. The connection structure between the circuit board and the battery adopts the connection structure between the circuit board and the battery described in Example 1, which can effectively improve the pad performance of the circuit board and improve the use effect of the entire battery pack.

[0026] In addition to the above preferred embodiments, the present invention has other implementation modes. Those skilled in the art can make various changes and modifications based on the present invention. As long as they do not depart from the spirit of the present invention, they should all fall within the scope defined by the claims attached to the present invention.

Claims

1. A connection structure between a circuit board and a battery, comprising a circuit board (1) and a battery assembly (2), wherein the battery assembly (2) is provided with a nickel sheet (3), and the nickel sheet (3) is provided with a pin (31), characterized in that: A connecting piece (11) is provided at the bottom end of the circuit board (1) and is fitted with the pin (31); an elastic clamp (21) is provided on the battery assembly (2); when the circuit board (1) is inserted into the elastic clamp (21), the connecting piece (11) and the pin (31) are fitted; the connecting piece (11) and the pin (31) are fixedly connected by laser welding; and a through hole (12) is provided on the circuit board (1) to facilitate laser welding of the connecting piece (11) and the pin (31).

2. The connection structure between a circuit board and a battery according to claim 1, characterized in that: The penetration hole (12) is a connection groove, and the connection groove is arranged on the side wall of the circuit board (1); or, the penetration hole (12) is a strip hole, and the strip hole is arranged on the circuit board (1).

3. The connection structure between a circuit board and a battery according to claim 2, characterized in that: The length of the through hole (12) is L1, and the length of the pin (31) is L2, wherein: 1.3L2≤L1≤1.4L2.

4. The connection structure between a circuit board and a battery according to claim 1, characterized in that: The circuit board (1) is provided with a positioning groove (13) adapted to the connecting piece (11).

5. The connection structure between a circuit board and a battery according to claim 4, characterized in that: The connecting piece (11) is a copper-tin alloy connecting piece or a nickel-plated steel strip connecting piece or a nickel connecting piece, and the thickness of the connecting piece (11) is equal to the thickness of the pin (31).

6. The connection structure between a circuit board and a battery according to claim 1, characterized in that: A positioning structure (4) is provided between the battery assembly (2) and the circuit board (1), and the positioning structure (4) comprises a positioning column (41) and a positioning hole (42) which are connected to each other.

7. The connection structure between a circuit board and a battery according to claim 6, characterized in that: The positioning column (41) is arranged on the battery assembly (2), and the positioning column (41) is arranged in a vertical direction or a horizontal direction, the positioning hole (42) is arranged on the circuit board (1), and the top end of the positioning column (41) is provided with an arc chamfer (43).

8. The connection structure between a circuit board and a battery according to claim 1, characterized in that: The elastic clamp (21) comprises a locking block (22) and a spring sheet (23); the locking block (22) is fixedly connected to the battery assembly (2) via the spring sheet (23); and the locking block (22) is provided with an inclination angle (24).

9. The connection structure between a circuit board and a battery according to claim 1, characterized in that: A short-circuit protection nickel sheet (5) is provided between the circuit board (1) and the battery assembly (2), and an opening (14) corresponding to the short-circuit protection nickel sheet (5) is provided on the circuit board (1).

10. A battery pack, comprising a housing and a connection structure between a circuit board and a battery disposed in the housing, characterized in that: The connection structure between the circuit board and the battery adopts the connection structure between the circuit board and the battery according to any one of claims 1-9.

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