Fuse structure and battery pack

Abstract

The utility model discloses a fuse structure and a battery pack. The fuse structure comprises a printed circuit board 1, an etching fuse 2 arranged on the printed circuit board 1, a bonding pad 3 arranged on the printed circuit board 1 and connected with one end of the etching fuse 2, and a metal sheet 4 connected to the printed circuit board 1 and connected with the other end of the etching fuse 2, the upper layer of the printed circuit board 1 is a welding area, and the lower layer is a hard insulating material; the metal sheet 4 is bent into a step shape at a right angle, and the upper step is connected with the upper layer of the printed circuit board 1 and is connected with the etching fuse 2; and the lower step is flush with the bottom of the printed circuit board 1. The utility model has the beneficial effects that the height is reduced, so that the product structure becomes compact; the lower layer of the printed circuit board is made of a hard insulating material, assembly is simple, and reliable insulation is ensured; the connection compatibility of the metal sheet and the battery pack aluminum bar is high, and the impedance is small; the mechanical strength is high and the service life is long; the production cost is low.

Description

Technical Field

[0001] This application relates to the field of electronic technology, specifically to a fuse structure and a battery pack. Background Technology

[0002] With the rapid development of new energy vehicles, power batteries are essential components, and their safety remains a critical issue. Currently, integrated busbars (Cells Contact System, CCS) use flexible printed circuit boards (FPCs) to collect and transmit electrical signals such as voltage, current, and temperature, integrating fuses onto the FPC. This is because fuse functionality can be easily implemented on FPCs; however, FPCs are relatively expensive.

[0003] When using lower-cost flexible flat cables (FFC) or wire harnesses to collect and transmit electrical signals, fuses cannot be integrated, and the entire CCS lacks fuse functionality. This results in less effective thermal management of the battery pack, and the circuit cannot be promptly cut off by a fuse in case of abnormal current.

[0004] However, if a fuse is to be installed on an FFC, the structure and materials of the fuse need to be improved because the installation structure requires a very compact design.

[0005] Therefore, there is an urgent need to develop a fuse structure and battery pack that is compact, easy to assemble, and safe and reliable. Utility Model Content

[0006] This application aims to solve the aforementioned technical problems.

[0007] Therefore, the first objective of this application is to provide a fuse structure that is compact, easy to assemble, and safe and reliable.

[0008] The second objective of this application is to propose a battery pack.

[0009] To achieve the above objectives, this application discloses a fuse structure, including a printed circuit board 1, an etched fuse 2 disposed on the printed circuit board 1, a solder pad 3 disposed on the printed circuit board 1 and connected to one end of the etched fuse 2, and a metal sheet 4 connected to the printed circuit board 1 and connected to the other end of the etched fuse 2; wherein, the upper layer of the printed circuit board 1 is a soldering area, and the lower layer is a rigid or flexible insulating material; the metal sheet 4 is bent at a right angle into a stepped shape, the upper step is connected to the upper layer of the printed circuit board 1 and to the etched fuse 2; the lower step is flush with the bottom of the printed circuit board 1.

[0010] In addition, the fuse structure according to the above-described technical solution of this application may also have the following additional technical features:

[0011] Optionally, the printed circuit board 1 and the metal sheet 4 are connected by surface mount, soldering, or laser welding processes.

[0012] Optionally, a through-hole 5 is provided at the connection between the metal sheet 4 and the printed circuit board 1.

[0013] To achieve the above objectives, a second aspect of this application provides a battery pack including a fuse structure as described in the first aspect of this application.

[0014] The beneficial effects of this application are as follows: 1. The fuse is etched into the printed circuit board, reducing the height and making the product structure more compact; 2. The lower layer of the printed circuit board is a rigid insulating material, which simplifies assembly and ensures reliable insulation; 3. The metal sheet has high compatibility with the battery pack aluminum bar and low impedance; 4. High mechanical strength and long service life; 5. Low production cost. Attached Figure Description

[0015] Figure 1 This is a perspective view of a fuse structure provided in one embodiment of this application;

[0016] Figure 2 This is a design drawing of a fuse structure provided in one embodiment of this application, wherein... Figure 2 (a) is the front view. Figure 2 (b) is a bottom view. Figure 2 (c) is a three-dimensional image.

[0017] Figure label:

[0018] 1-Printed circuit board, 2-Etched fuse, 3-Solder pad, 4-Metal sheet, 5-Through-tin hole. Detailed Implementation

[0019] The embodiments of this application are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or parts / elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this application, and should not be construed as limiting this application.

[0020] The fuse structure of this application embodiment is described below with reference to the accompanying drawings.

[0021] Figure 1 This is a perspective view of a fuse structure provided in one embodiment of this application; Figure 2 This is a design drawing of a fuse structure provided in one embodiment of this application, wherein... Figure 2(a) is the front view. Figure 2 (b) is a bottom view. Figure 2 (c) is a 3D diagram. For example... Figure 1-2 As shown: The fuse structure includes a printed circuit board 1, an etched fuse 2 disposed on the printed circuit board 1, a solder pad 3 disposed on the printed circuit board 1 and connected to one end of the etched fuse 2, and a metal sheet 4 connected to the printed circuit board 1 and connected to the other end of the etched fuse 2; wherein, the upper layer of the printed circuit board 1 is a soldering area, and the lower layer is a rigid or flexible insulating material; the metal sheet 4 is bent at a right angle into a stepped shape, the upper step is connected to the upper layer of the printed circuit board 1 and to the etched fuse 2; the lower step is flush with the bottom of the printed circuit board 1.

[0022] Specifically, metal sheet 4 is made of metal, typically nickel, steel, aluminum, or copper, and can be welded to materials such as battery pack aluminum bars. This material selection improves the welding compatibility between metal sheet 4 and battery pack aluminum bars, reduces interface impedance, and enhances current transmission stability. Circuit board 1 is a rigid printed circuit board material. The upper layer is the solder pad, i.e., the soldering area, which can be used to solder components such as FFCs or wire harnesses. The lower layer is the insulating material of the rigid printed circuit board, ensuring insulation from the aluminum bars or other metal structures of the battery pack below. It can be placed directly or attached to components such as aluminum bars using double-sided adhesive. The insulating material of the printed circuit board provides mechanical support, preventing connection failures caused by deformation of flexible materials, while also keeping the printed circuit board insulated from the aluminum bus or other components below. Alternatively, depending on the battery pack design requirements, such as the need for a buffer function, the lower layer of the printed circuit board can be made of a soft material. The pad 3 is made of bare copper or tin-plated material, which can be used to solder components such as FFC or wire harnesses, making the soldering connection convenient and reliable. The fuse 2 is a fine line etched using FPC technology. It functions as a fuse according to different current fusing requirements, and can melt when the current is abnormal.

[0023] Firstly, the flush-mounted step design with the PCB allows for direct mounting to the battery pack aluminum frame or module housing, avoiding the extra space required by traditional vertical soldering. This enables a bracket-free CCS structure, eliminating the bracket components for fixing metal plates in traditional CCS, reducing the number of parts and assembly complexity. This results in better product space adaptability. This design can save 5-8mm of vertical space for the product.

[0024] Secondly, it boasts excellent mechanical stability: the metal sheet forms a physically interlocked structure through right-angle bending, resulting in a relatively stable structure. Regarding impact resistance, the lower step, flush with the bottom of the PCB, creates an "L"-shaped support between the metal sheet and the PCB, resisting high-frequency vibrations during battery pack operation (such as the bumpy conditions of new energy vehicles) and preventing fatigue fracture of solder joints (compared to an unbent cantilever structure). In terms of welding strength, the connection point between the upper step and the upper layer of the PCB is directly welded to the etched fuse, while the contact surface between the lower step and the aluminum bar is fixed through laser welding or riveting, forming a double anchoring point and reducing the risk of single-point failure. Furthermore, the lower step of the metal sheet is flush with the bottom of the PCB, achieving a large-area contact with the aluminum bar. The aluminum bar is generally a flat structure, connecting to the metal sheet on one side and supporting the printed circuit board on the other, eliminating the need for additional components or an uneven structure. Vibration test results show that this fuse structure increases lifespan by approximately three times.

[0025] Finally, the metal sheet can be formed in one step through stamping, simplifying the processing. Furthermore, the pre-formed stepped structure of the metal sheet allows for direct positioning during SMT soldering, avoiding precision errors caused by on-site bending. This reduces the overall FFC production cost by approximately 15% to 20%.

[0026] According to the fuse structure of this application, the fuse is fabricated directly on the printed circuit board through an etching process (instead of the dedicated process of FPC), which further simplifies the manufacturing process and reduces production costs; it allows the use of FFC or ordinary wire harnesses as signal transmission carriers, breaking through the dependence of traditional FPC on fuse integration; the etching process can precisely control the line width, thickness and shape of the fuse, and achieve a fast melting response for specific current values. Compared with traditional alloy fuses, the geometric parameters of etched lines are more adjustable, which can meet the diverse overcurrent protection requirements of battery packs; the rigid printed circuit board provides mechanical support and also has an insulating effect, saving intermediate materials.

[0027] According to one embodiment of this application, the printed circuit board 1 and the metal sheet 4 are connected by surface mount technology (SMT), soldering, or laser welding.

[0028] Specifically, the metal sheet 4 can be connected to the printed circuit board 1 using SMT (Surface Mount Technology), which can effectively reduce the product size and save production costs. Laser welding can also be used, due to its small heat-affected zone, concentrated and rapid heating, and low thermal stress. Traditional soldering or other methods can also be used.

[0029] According to one embodiment of this application, a through-hole 5 is provided at the connection between the metal sheet 4 and the printed circuit board 1.

[0030] Specifically, when the metal sheet is welded to the aluminum bar, the hole facilitates solder penetration, ensuring reliable welding; and it also allows gases generated during welding to escape, ensuring a reliable weld connection.

[0031] Based on the above embodiments, this invention also proposes a battery pack, including: a fuse structure as described in the above embodiments.

[0032] According to a battery pack of this application, the fuse structure is fabricated directly on the printed circuit board using an etching process (instead of a dedicated process for FPC), further simplifying the manufacturing process and reducing production costs; it allows the use of FFC or ordinary wire harnesses as signal transmission carriers, breaking through the dependence of traditional FPCs on fuse integration; the etching process allows for precise control of the fuse's line width, thickness, and shape, achieving rapid fusing response for specific current values. Compared to traditional alloy fuses, the geometric parameters of etched circuits are more adjustable, meeting the diverse overcurrent protection requirements of the battery pack; the rigid printed circuit board provides mechanical support while also serving as insulation, saving intermediate materials.

[0033] The above embodiments are preferred implementations of this application. In addition, this application can be implemented in other ways. Any obvious substitutions without departing from the concept of this application are within the protection scope of this application.

Claims

1. A fuse structure, characterized by, The application relates to a fuse structure integrated wiring harness busbar structure. The application relates to a fuse structure integrated wiring harness busbar structure. The application relates to a fuse structure integrated wiring harness busbar structure. The application relates to a fuse structure integrated wiring harness busbar structure.

2. The fuse structure of claim 1, wherein: ​ 3. A battery pack, characterized by: ​

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