A sampling assembly and battery pack

Abstract

The utility model provides a kind of sampling assembly and battery pack, the sampling assembly includes support, busbar and flexible circuit board;Wherein, the busbar is set in the support, the support is equipped with connecting portion, and the connecting portion is used to be connected with battery management system;The flexible circuit board includes circuit board ontology, and the circuit board ontology has first bending part and second bending part, the first bending part is bent to the direction of busbar, the first bending part is electrically connected with the busbar, the second bending part is bent to the direction of connecting portion, and the second bending part is used to be electrically connected with the battery management system.In the application, flexible circuit board with foldable is connected with busbar, signal acquisition and transmission are carried out, flexible circuit board has better high-temperature resistance and short-circuit prevention, has good working performance in large-scale fire test, and can meet the thermal runaway test requirements of product.

Description

Technical Field

[0001] This application belongs to the field of battery technology, specifically relating to a sampling component and a battery pack. Background Technology

[0002] A sudden temperature rise inside a lithium-ion battery due to a short circuit, overcharging, or mechanical damage can trigger a chain reaction, including electrolyte decomposition and separator melting, potentially leading to an explosive combustion. Therefore, specialized thermal runaway testing is necessary for battery packs containing lithium-ion batteries to assess whether thermal runaway in a single lithium-ion cell could propagate to the entire battery pack, posing a risk of larger-scale fires or explosions.

[0003] When lithium-ion batteries experience thermal runaway, they release a large amount of heat. The wiring harness used for sampling in the battery pack has poor high-temperature resistance and is prone to melting or short-circuiting under the high temperatures generated by thermal runaway, resulting in interruption or distortion of the sampling signal and affecting the accuracy of the test results. Utility Model Content

[0004] This invention provides a sampling component and a battery pack, aiming to solve the problem of poor high-temperature resistance of the wire harness used for sampling in the battery pack in the prior art.

[0005] In a first aspect, this utility model embodiment provides a sampling component, which includes a bracket, a busbar, and a flexible circuit board; wherein,

[0006] The busbar is disposed on the bracket, and the bracket is provided with a connecting part for connecting to the battery management system;

[0007] The flexible circuit board includes a circuit board body, which has a first bending portion and a second bending portion. The first bending portion bends toward the busbar and is electrically connected to the busbar. The second bending portion bends toward the connection portion and is used to be electrically connected to the battery management system.

[0008] Optionally, there may be multiple flexible circuit boards, which are stacked on the support along a first direction.

[0009] Optionally, the first bent portions of the plurality of flexible circuit boards are spaced apart on the support, and the plurality of flexible circuit boards are electrically connected to adjacent busbars respectively.

[0010] Optionally, the second bending portions of a plurality of the flexible circuit boards are stacked along the first direction on the connecting portion.

[0011] Optionally, the first bend is provided with at least one connecting piece, and each connecting piece is connected to one of the busbars.

[0012] Optionally, the second bend is provided with a connector terminal for electrical connection with the battery management system.

[0013] Optionally, there are multiple flexible circuit boards, and each of the second bends has a different dimension along its extension direction, so that the connector terminals on the multiple second bends are arranged sequentially on the connection portion.

[0014] Optionally, the bracket is provided with a receiving groove, and the flexible circuit board is embedded in the receiving groove, the shape of which is adapted to the shape of the first bending portion and the second bending portion.

[0015] Optionally, the flexible circuit board includes a fuse.

[0016] Secondly, this utility model embodiment also provides a battery pack, including any of the sampling components provided in the first aspect.

[0017] This embodiment of the invention connects a flexible circuit board to the busbar of the battery pack for signal acquisition and transmission. The flexible circuit board has better high-temperature resistance and short-circuit protection, and performs well in large-scale fire tests, ensuring the stability of signal transmission and meeting the thermal runaway test requirements of the product. The flexible circuit board is bent to fit the wiring of the busbar and support within the battery pack, saving space and eliminating the need for redesigning and molding the busbar and support, thus reducing production costs.

[0018] 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

[0019] 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:

[0020] Figure 1 This is a schematic diagram of a sampling component according to an embodiment of the present utility model;

[0021] Figure 2 yes Figure 1 A top view of the sampling component shown;

[0022] Figure 3 This is a stacked schematic diagram of flexible circuit boards according to an embodiment of the present utility model;

[0023] Figure 4 yes Figure 3 The center circle shows a magnified view of part A.

[0024] Figure 5 yes Figure 3 A top view of the flexible circuit board shown;

[0025] Figure 6 This is a schematic diagram of an unbent flexible circuit board according to an embodiment of the present utility model;

[0026] Figure 7 This is a schematic diagram of a flexible circuit board after bending according to an embodiment of the present invention.

[0027] Reference numerals: 10: bracket; 11: connecting part; 20: busbar; 30: flexible circuit board; 31: first bending part; 311: connecting piece; 32: second bending part; 321: connector terminal; 33: first flexible circuit board; 34: second flexible circuit board; 35: third flexible circuit board; 36: fourth flexible circuit board. Detailed Implementation

[0028] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those skilled in the art without creative effort are within the fixed scope of the present utility model.

[0029] It should be understood that the phrase "one embodiment" or "an embodiment" throughout the specification means that a specific feature, structure, or characteristic related to the embodiment is included in at least one embodiment of the present invention. Therefore, "in one embodiment" or "in an embodiment" appearing throughout the specification do not necessarily refer to the same embodiment. Furthermore, these specific features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.

[0030] Battery thermal runaway refers to the abnormal increase in local temperature caused by factors such as internal short circuits, overcharging, overheating, and physical damage inside a lithium-ion battery. This triggers a series of violent chemical reactions, including electrolyte decomposition, positive and negative electrode material reactions, and separator melting and shrinkage. In a short period of time, a large amount of heat and flammable gas are released. The heat generated further accelerates the reaction. Thermal runaway of a single lithium-ion battery can quickly spread to the entire battery pack, forming an unstoppable chain reaction. Ultimately, this leads to a sharp rise in the battery pack temperature, causing accidents such as fires and explosions.

[0031] Therefore, specialized thermal runaway testing is required for battery packs containing lithium-ion batteries to assess whether thermal runaway in a single lithium-ion battery will spread to the entire battery pack, potentially leading to a larger-scale fire or explosion. Battery packs typically use wiring harnesses to connect the batteries to the battery management system (BMS) to collect data such as voltage and temperature. Under normal operating conditions, these harnesses are sufficient for data acquisition. However, during thermal runaway, lithium-ion batteries release a significant amount of heat. The wiring harnesses used for sampling in the battery pack have poor high-temperature resistance, operating below 200°C. Under the high temperatures generated by thermal runaway, they are prone to melting or short-circuiting, causing signal interruption or distortion and affecting the accuracy of the test results.

[0032] This utility model provides a sampling assembly that solves the problem of poor high-temperature resistance of the wiring harness used for sampling in the battery pack in the prior art. The sampling assembly includes a bracket 10, a busbar 20, and a flexible circuit board 30; wherein, the busbar 20 is disposed on the bracket 10, and the bracket 10 is provided with a connecting part 11 for connecting with the battery management system; the flexible circuit board 30 includes a circuit board body, the circuit board body having a first bending part 31 and a second bending part 32, the first bending part 31 bends toward the busbar 20 and is electrically connected to the busbar 20, the second bending part 32 bends toward the connecting part 11 and is electrically connected to the battery management system.

[0033] like Figure 1 As shown in Figure 2, the sampling component consists of a bracket 10, a busbar 20, and a flexible circuit board 30. The bracket 10 is used to fix the sampling component and insulate each charged component. The busbar 20 is welded to the battery cell terminal. One end of the flexible circuit board 30 is connected to the busbar 20, and the other end is connected to the battery management system to collect information such as the battery's current, voltage, and temperature.

[0034] In practical applications, multiple battery cell arrays are distributed within the battery pack housing. A support frame 10 is positioned above the battery cells, and busbars 20 are correspondingly mounted on the support frame 10 for each battery cell. Busbars 20 can be made of aluminum, copper, or a copper-aluminum composite material. The busbars 20 are connected to the battery cell terminals via welding, achieving electrical connection between the battery cells and the sampling components. Signals are then transmitted to the battery management system via a flexible circuit board 30. The flexible circuit board 30 can be bent, folded, and twisted, facilitating wiring on the support frame 10 and preventing interference from the structures on the support frame 10 and busbars 20. A connecting portion 11 is provided on the support frame 10, providing installation space for the flexible circuit board 30 and the battery management system. The connecting portion 11 is located at the end of the support frame 10 to avoid areas with dense electrical connections on the support frame 10. The connecting portion 11 can be made of epoxy board. One end of the flexible circuit board 30 is positioned on the connecting portion 11 and connected to the battery management system.

[0035] The flexible circuit board 30 is composed of a substrate and copper foil bonded together. The copper foil itself has a high melting point and good heat resistance. The substrate can be a high-temperature resistant substrate. The layered structure of the flexible circuit board 30 avoids the redundant structure of multiple independently insulated wires in the wire harness. It can withstand extreme instantaneous high temperatures, which is conducive to maintaining stable electrical performance in high-temperature environments. It is not easy to melt or short-circuit, and has a longer service life in thermal runaway testing, which is beneficial to data acquisition during the testing process.

[0036] Furthermore, since the flexible circuit board 30 can be bent, folded, and twisted, it can adapt well to the existing structure of the bracket 10 and bus 20, eliminating the need to redesign the bracket 10 and bus 20 and saving design and mold costs.

[0037] Specifically, the wiring of the flexible circuit board 30 can utilize the existing empty structure on the bracket 10. In this embodiment, the flexible circuit board 30 includes a flexible circuit board 30 body, which extends on the surface of the bracket 10 from the connecting portion 11 to the busbar 20. The flexible circuit board 30 body can extend along the side of the bracket 10 or at the middle of the bracket 10. This utility model does not limit the specific location of the flexible circuit board 30. The flexible circuit board 30 is bent at least twice at both ends to form a first bending portion 31 and a second bending portion 32. The first bending portion 31 bends towards the busbar 20 and is electrically connected to the busbar 20. The second bending portion 32 extends towards the connecting portion 11 and is connected to the battery management system.

[0038] In this embodiment, as Figure 2 As shown, busbars 20 are welded to the two terminals of the battery cell, and the first bend 31 is arranged using the space between the busbars 20. Since an explosion-proof valve is installed between the terminals, a hole is cut in the first bend 31 opposite to the explosion-proof valve to avoid it, ensuring that gas and liquid inside the battery cell can be released normally through the explosion-proof valve. The specific shape of the first bend 31 is related to the layout of the bracket 10 and the busbars 20. The layout scheme given in this embodiment is only an example and should not be considered as a limitation on the shape of the first bend 31.

[0039] Accordingly, the main body of the flexible circuit board 30 can be bent three, four, or any number of times. The specific bending position is also related to the actual layout of the bracket 10 and the busbar 20. Based on this embodiment, the main body of the flexible circuit board 30 can also be bent multiple times between the first bending part 31 and the second bending part 32 to avoid the existing structure of the bracket 10 and the busbar 20. The wiring of the flexible circuit board 30 is completed without changing the structure of the bracket 10 and the busbar 20, and the busbar 20 is connected to the battery management system.

[0040] In this embodiment of the invention, the sampling component uses a flexible circuit board 30 to achieve the electrical connection between the busbar 20 and the battery management system. This effectively improves the high-temperature resistance of the sampling harness and avoids melting or short circuits in high-temperature environments, thus ensuring the safe operation of the battery pack. Furthermore, the design of the flexible circuit board 30 makes the sampling component more compact, reducing space occupation and improving the integration and reliability of the battery pack. The design in this invention can be directly applied to existing battery pack sampling components; only the harness needs to be replaced with the flexible circuit board 30, and bent, stacked, or twisted according to the structure of the bracket 10 and busbar 20. This saves on redesign and mold-making costs and meets the existing wiring and product performance requirements of the bracket 10 and busbar 20.

[0041] In some alternative embodiments, there are multiple flexible circuit boards 30, which are stacked on the support 10 along the first direction.

[0042] When the battery pack is large and contains a large number of cells, multiple flexible circuit boards 30 can be installed inside the battery pack. Each flexible circuit board 30 is responsible for sampling a portion of the cells, which facilitates wiring and further enhances the stability and reliability of the entire sampling assembly. This design also facilitates later maintenance and replacement. When a flexible circuit board 30 fails, it can be replaced individually without affecting the normal operation of other parts, thereby reducing maintenance costs and time.

[0043] like Figure 2 As shown in Figure 4, in this embodiment, multiple flexible circuit boards 30 are stacked along a first direction, which refers to the thickness direction of the support 10, i.e., the height direction of the battery pack. This fully utilizes the internal space of the battery pack, making the battery pack structure more compact and improving space utilization. Furthermore, the stacking method of the multiple flexible circuit boards 30 can be flexibly adjusted according to actual needs to adapt to battery packs of different sizes and structures, improving the applicability and flexibility of the sampling component in this embodiment.

[0044] It should be noted that the flexible circuit board 30 is composed of copper foil and an insulating substrate laminated together, which insulates the multiple stacked flexible circuit boards 30 from each other. Specifically, the substrate is usually made of polyimide film or polyester film, and both sides of the copper foil are covered by the substrate, effectively insulating the copper foil used for signal transmission within the flexible circuit board 30 from the external environment. This ensures that the multiple stacked flexible circuit boards 30 are insulated from each other, and each flexible circuit board 30 can be connected independently without interfering with adjacent flexible circuit boards 30.

[0045] In some alternative embodiments, the first bends 31 of a plurality of flexible circuit boards 30 are spaced apart on the support 10, and the plurality of flexible circuit boards 30 are electrically connected to adjacent busbars 20 respectively.

[0046] When the battery pack is large, the first bends 31 of the multiple flexible circuit boards 30 should be distributed at various locations on the support 10, connecting to the nearest adjacent busbar 20. Specifically, the battery pack is typically cuboid, and the multiple flexible circuit boards 30 can be distributed along the length of the battery pack, i.e., the length of the support 10. Understandably, in this wiring method, the first bends 31 of the multiple flexible circuit boards 30 will necessarily be located at different positions, and the various first bends 31 are spaced apart.

[0047] like Figure 2 As shown, in this embodiment, a flexible circuit board 30 is arranged between every two rows of cells, and the first bent portion 31 of the flexible circuit board 30 is electrically connected to the busbars 20 on both sides. This layout not only reduces the length and complexity of the lines, but also improves sampling efficiency and accuracy. The bending or folding shape of the first bent portion 31 allows it to flexibly adapt to different positions on the bracket 10, ensuring good electrical contact with the busbars 20.

[0048] In some alternative embodiments, the second bending portions 32 of a plurality of flexible circuit boards 30 are stacked along the first direction on the connecting portion 11.

[0049] In this embodiment, the stacking arrangement refers to partial stacking. The second bending portions 32 of multiple flexible circuit boards 30 are all connected to the battery management system through the connecting portion 11. The stacking is mainly between the second bending portion 32 and the first bending portion 31 and the second bending portion 32. The portions of multiple flexible circuit boards 30 other than the first bending portion 31 can share the wiring space.

[0050] By stacking multiple flexible circuit boards 30 at the second bend 32, the volume occupied by the sampling components in the battery pack can be significantly reduced, making more efficient use of limited space resources and resulting in a more compact and efficient internal structure of the battery pack. This provides greater flexibility and possibilities for the arrangement of other components and is applicable to battery packs of different specifications and models.

[0051] In some alternative embodiments, the first bend 31 is provided with at least one connecting piece 311, each connecting piece 311 being connected to a busbar 20.

[0052] The connecting piece 311 is a conductive metal sheet such as a nickel sheet or a copper sheet, which is soldered to the surface of the busbar. Depending on the number of busbars 20 connected to the flexible circuit board 30, multiple connecting pieces 311 can be provided on the first bend 31.

[0053] In some alternative embodiments, the second bend 32 is provided with a connector terminal 321 for electrical connection with the battery management system.

[0054] Connector terminal 321 can be configured with a plug-in type compatible with the battery management system, facilitating quick and accurate electrical connection. The position and number of connector terminals 321 can be adjusted according to actual needs to meet the design requirements of different battery packs.

[0055] In addition, in some alternative embodiments, there are multiple flexible circuit boards 30, and each second bend 32 has a different size along its extension direction, so that the connector terminals 321 on the multiple second bends 32 are arranged sequentially on the connection portion 11.

[0056] like Figure 3 As shown in Figure 5, the connector terminal 321 is located at the end of the second bend 32 away from the first bend 31. The lengths of the second bends 32 of the multiple flexible circuit boards 30 are different, so that the connector terminals 321 on each second bend 32 are staggered, which facilitates installation and connection.

[0057] In some alternative embodiments, the support 10 is provided with a receiving groove, and the flexible circuit board 30 is embedded in the receiving groove, the shape of which is adapted to the shape of the first bending portion 31 and the second bending portion 32.

[0058] Utilizing the inherent structure on the support 10 as a receiving groove not only provides stable support for the flexible circuit board 30 but also effectively protects it from interference and damage from the external environment. By adapting the shapes of the first bending portion 31 and the second bending portion 32 to the shape of the receiving groove, the stability and reliability of the flexible circuit board 30 within the receiving groove can be ensured, preventing loosening or detachment during use. This helps optimize the structural layout of the entire sampling assembly, making it more compact and rational.

[0059] Additionally, in some alternative embodiments, a fuse is provided within the flexible circuit board 30.

[0060] The flexible circuit board 30 contains a fuse that melts and provides protection in the event of a short circuit in the battery pack. When a specific circuit within the battery pack malfunctions, the corresponding fuse melts promptly, preventing the fault from spreading and ensuring the overall safety of the battery pack.

[0061] like Figure 6As shown, the sampling component in this embodiment includes four stacked flexible circuit boards 30, namely a first flexible circuit board 33, a second flexible circuit board 34, a third flexible circuit board 35, and a fourth flexible circuit board 36. The flexible circuit boards 30 are formed using a mold. Based on the distance between the first bending portion 31 and the connecting portion 11 of each flexible circuit board 30, each flexible circuit board 30 has a different length, with the first flexible circuit board 33 being the shortest and the fourth flexible circuit board 36 being the longest. The flexible circuit boards 30 are bent at two points in the same direction at 180 degrees to reduce waste and save costs. After being pressed together with the connecting piece 311 and the connector terminal 321, they form a single unit.

[0062] like Figure 7 As shown, the first flexible circuit board 33, the second flexible circuit board 34, the third flexible circuit board 35, and the fourth flexible circuit board 36, after being formed, are stacked in sequence. The second bending portion 32 of the four flexible circuit boards 30 is provided at the connecting portion 11, and after bending, it extends. When it extends to the designed length, the flexible circuit board 30 is bent towards the busbar 20 to form the first bending portion 31. The other flexible circuit boards 30 continue to extend until all four flexible circuit boards 30 have completed bending.

[0063] Then, the connected flexible circuit board 30 and connecting part 11 are glued to the plastic bracket 10 with adhesive, and the connecting piece 311 is welded to the surface of the busbar 20. The sampling component is then assembled onto the battery pack, and the busbar 20 is laser welded to the cell terminal. The connector terminal 321 of the second bend 32 is connected to the battery management system via an adapter cable.

[0064] In practical applications, the number of flexible circuit boards 30 can be arbitrarily changed according to the volume of the battery pack and the number of cells. The flexible circuit boards 30 are set according to the above method to improve the high temperature resistance of the sampling component.

[0065] In this embodiment of the invention, a flexible circuit board 30 is connected to the busbar 20 of the battery pack for signal acquisition and transmission. The flexible circuit board 30 has better high-temperature resistance and short-circuit protection, and performs well in large-scale fire tests, ensuring the stability of signal transmission and meeting the thermal runaway test requirements of the product. The flexible circuit board 30 is bent to fit the wiring of the busbar 20 and the bracket 10 within the battery pack, saving space and eliminating the need for redesigning and remolding the busbar 20 and the bracket 10, thus reducing production costs.

[0066] This utility model embodiment also provides a battery pack, including any of the sampling components provided in the above embodiments.

[0067] The battery pack in this embodiment has the same advantages as the sampling component described above, and will not be further explained here.

[0068] It should be noted that the various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0069] Although alternative embodiments of the present invention have been described, those skilled in the art, upon learning the basic inventive concept, can make further changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the alternative embodiments as well as all changes and modifications falling within the scope of the present invention.

[0070] Finally, it should be noted that in this document, relational terms such as "first" and "second" are used merely to distinguish one entity from another, and do not necessarily require or imply any such actual relationship or order between these entities. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that an article or terminal device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such an article or terminal device. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the article or terminal device that includes that element.

[0071] The technical solution provided by this utility model has been described in detail above. Specific examples have been used to illustrate the principle and implementation of this utility model. At the same time, for those skilled in the art, there will be changes in the specific implementation and application scope based on the principle and implementation of this utility model. Therefore, the content of this specification should not be construed as a limitation of this utility model.

Claims

1. A sampling component, characterized in that, The sampling assembly includes a bracket (10), a busbar (20), and a flexible circuit board (30); wherein, The busbar (20) is disposed on the bracket (10), and the bracket (10) is provided with a connecting part (11), which is used to connect to the battery management system; The flexible circuit board (30) includes a circuit board body, which has a first bending portion (31) and a second bending portion (32). The first bending portion (31) bends toward the busbar (20) and is electrically connected to the busbar (20). The second bending portion (32) bends toward the connecting portion (11) and is used to be electrically connected to the battery management system.

2. The sampling component according to claim 1, characterized in that, The number of flexible circuit boards (30) is multiple, and the multiple flexible circuit boards (30) are stacked on the support (10) along the first direction.

3. The sampling component according to claim 2, characterized in that, The first bends (31) of the plurality of flexible circuit boards (30) are spaced apart on the support (10), and the plurality of flexible circuit boards (30) are electrically connected to the adjacent busbars (20).

4. The sampling component according to claim 3, characterized in that, The second bending portions (32) of a plurality of the flexible circuit boards (30) are stacked on the connecting portion (11) along the first direction.

5. The sampling component according to claim 1, characterized in that, The first bend (31) is provided with at least one connecting piece (311), and each connecting piece (311) is connected to one of the busbars (20).

6. The sampling component according to claim 1, characterized in that, The second bend (32) is provided with a connector terminal (321), which is used to electrically connect to the battery management system.

7. The sampling component according to claim 6, characterized in that, The number of flexible circuit boards (30) is multiple, and each of the second bends (32) has a different size along its extension direction, so that the connector terminals (321) on the multiple second bends (32) are arranged sequentially on the connection portion (11).

8. The sampling component according to claim 1, characterized in that, The bracket (10) is provided with a receiving groove, and the flexible circuit board (30) is embedded in the receiving groove. The shape of the receiving groove is adapted to the shape of the first bending part (31) and the second bending part (32).

9. The sampling component according to claim 1, characterized in that, The flexible circuit board (30) is equipped with a fuse.

10. A battery pack, characterized in that, Includes the sampling component as described in any one of claims 1-9.

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