Circuit board structure, battery cell assembly and lithium ion battery

Abstract

The invention provides a circuit board structure, a battery cell assembly and a lithium ion battery, and relates to the technical field of batteries. The circuit board structure provided by the embodiment of the invention comprises a flexible circuit board and a plurality of nickel sheets, the plurality of nickel sheets are alternately distributed on two sides of the flexible circuit board along the length direction of the flexible circuit board, and the flexible circuit board between any group of adjacent nickel sheets is provided with a wave-shaped bending part along the length direction of the flexible circuit board. According to the circuit board structure provided by the embodiment of the invention, the bending part which is bent in the wave shape on the flexible circuit board can fully absorb the stress on the flexible circuit board caused by the expansion and contraction of the battery cell and the like, so that the flexible circuit board is prevented from being broken, a cantilever structure does not need to be etched on the circuit board, and the manufacturing process of the circuit board structure is effectively simplified.

Description

Circuit board structure, cell assembly and lithium-ion battery Technical Field

[0001] This invention relates to the field of battery technology, and in particular to a circuit board structure, a cell assembly, and a lithium-ion battery. Background Technology

[0002] FPC (Flexible Printed Circuit) is the core carrier for signal transmission and sampling inside lithium-ion batteries. To address the breakage of FPC under impact, tension, or repeated tension (caused by the periodic expansion and contraction deformation of the battery cell), the current practice is to set a notch at the connection between the FPC body and the nickel sheet and etch a cantilever structure between the FPC body and the nickel sheet. This cantilever structure absorbs the stress generated by the expansion and contraction of the battery cell, thus preventing FPC breakage.

[0003] However, cantilever structures are usually slender, curved, or suspended in some areas, and the area where they connect with the nickel sheet is small and stress is concentrated. Therefore, the etching process of cantilever structures is difficult, and the flow rate and reaction time of the etching solution in the etching area are likely to differ from those in other areas, which can easily lead to over-etching of the cantilever structure or incomplete etching of the nickel sheet area. Summary of the Invention

[0004] The purpose of this invention is to provide a circuit board structure, a battery cell assembly, and a lithium-ion battery to alleviate the technical problems in the prior art, such as the difficulty of etching the cantilever structure on the flexible printed circuit board, the easy difference in the flow rate of the etching solution and the reaction time of the etching area compared with other areas, which easily leads to over-etching of the cantilever structure or incomplete etching of the nickel sheet area.

[0005] In a first aspect, the present invention provides a circuit board structure, the circuit board structure comprising a flexible circuit board and a plurality of nickel sheets; the plurality of nickel sheets are alternately distributed on both sides of the flexible circuit board along the length direction of the flexible circuit board, and along the length direction of the flexible circuit board, the flexible circuit board between any two adjacent nickel sheets is provided with a wavy bend.

[0006] In an optional embodiment, a plurality of bending portions are provided from the middle of the flexible circuit board to any one of its ends, and the maximum peak of the plurality of bending portions on either side of the middle of the flexible circuit board increases sequentially from the middle to the end of the flexible circuit board.

[0007] In an optional embodiment, from one end of the flexible circuit board to the other, the troughs of the multiple bends on the flexible circuit board are all equal, so that the flexible circuit board surfaces at the troughs of the multiple bends are all located on the same horizontal plane.

[0008] In an optional embodiment, the bend between any two adjacent nickel sheets has a peak.

[0009] In an optional embodiment, the flexible circuit board at the crest of each bend is a quadrilateral plate structure.

[0010] In an optional embodiment, the plate surfaces on both sides of any corner of the bend are smoothly connected.

[0011] In an optional embodiment, the number of bends on one side of the middle portion of the flexible circuit board is equal to the number of bends on the other side of the middle portion of the flexible circuit board.

[0012] In an optional embodiment, the bent portion on one side of the middle portion of the flexible circuit board and the bent portion on the other side of the middle portion of the flexible circuit board are symmetrically distributed with the center line of the flexible circuit board as the axis of symmetry.

[0013] In a second aspect, the present invention provides a battery cell assembly, the battery cell assembly comprising the circuit board structure described in any of the foregoing embodiments.

[0014] Thirdly, the present invention provides a lithium-ion battery, the lithium-ion battery comprising the cell assembly described in the foregoing embodiments.

[0015] The circuit board structure provided by this invention includes a flexible circuit board and multiple nickel sheets. The nickel sheets are alternately distributed on both sides of the flexible circuit board along its length, and each pair of adjacent nickel sheets along the length of the flexible circuit board has a wavy bend. This circuit board structure is a flexible printed circuit board for lithium-ion batteries. When preparing the circuit board structure provided in this embodiment, multiple wavy bends can be formed on the flexible circuit board through processes such as stamping and bending, depending on the connection position between the nickel sheets and the flexible circuit board. Therefore, when the flexible circuit board is mounted on multiple sequentially spaced battery cells via nickel sheets, if the battery cells undergo periodic expansion-contraction deformation or are subjected to impact or tension, the nickel sheets and the flexible circuit board deform accordingly. At this time, the wavy bends can deform and absorb the stress on the flexible circuit board, effectively preventing breakage of the flexible circuit board and improving the reliability of the lithium-ion battery, without the need to etch a cantilever structure on the flexible circuit board. Compared to the etching process of cantilever structures, the manufacturing process of the bending part is simpler. Therefore, the circuit board structure provided by the embodiments of the present invention can effectively simplify the manufacturing process of the circuit board structure and reduce the difficulty of the production process while improving the reliability of the circuit board structure.

[0016] Compared with the prior art, the circuit board structure provided by the present invention can fully absorb the stress generated by the expansion and contraction of the battery cells on the flexible circuit board through the bending part on the flexible circuit board, thereby preventing the flexible circuit board from breaking. There is no need to etch cantilever structure on the circuit board. It can improve the reliability of the circuit board structure while effectively simplifying the manufacturing process of the circuit board structure, reducing the difficulty of the production process, and improving the production efficiency.

[0017] The battery cell assembly provided by the present invention includes the above-described circuit board structure, and therefore the battery cell assembly has the same beneficial effects as the above-described circuit board structure.

[0018] The lithium-ion battery provided by the present invention includes the above-mentioned cell assembly, and therefore the lithium-ion battery has the same beneficial effects as the above-mentioned cell assembly. Attached Figure Description

[0019] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0020] Figure 1 is a schematic diagram of the circuit board structure provided in an embodiment of the present invention; Figure 2 is a side view of the battery cell assembly including the circuit board structure provided in an embodiment of the present invention.

[0021] Icons: 1-Flexible circuit board; 10-Bending section; 100-Crest; 101-Valley; 2-Nickel sheet; 3-Battery cell. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0023] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0024] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0025] In the description of this invention, it should be noted that the terms "center," "vertical," "horizontal," "upper," "lower," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship in which the product of this invention is usually placed when in use. They are only used to facilitate the description of this invention and to simplify the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0026] Furthermore, terms such as "horizontal," "vertical," and "sag" do not imply that components must be absolutely horizontal or suspended, but rather that they can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal relative to "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0027] In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0028] The following detailed description of some embodiments of the present invention is provided in conjunction with the accompanying drawings. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0029] Example: As shown in Figure 1, the circuit board structure provided in this embodiment of the invention includes a flexible circuit board 1 and a plurality of nickel sheets 2; the plurality of nickel sheets 2 are alternately distributed on both sides of the flexible circuit board 1 along the length direction of the flexible circuit board 1, and along the length direction of the flexible circuit board 1, the flexible circuit board 1 between any two adjacent nickel sheets 2 is provided with a wavy bending portion 10.

[0030] The circuit board structure provided in this embodiment of the invention can be a flexible printed circuit board in a lithium-ion battery. When manufacturing the circuit board structure provided in this embodiment of the invention, a wavy bending portion 10 can be provided on the flexible circuit board 1 by stamping, bending and other processes according to the connection position between the nickel sheet 2 and the flexible circuit board 1.

[0031] As shown in Figure 2, this embodiment of the invention also provides a battery cell assembly, which includes the aforementioned circuit board structure. The battery cell assembly further includes multiple battery cells 3 arranged in a sequentially spaced manner. A flexible circuit board 1 in the circuit board structure is connected to each of the multiple battery cells 3 through multiple nickel sheets 2, and the flexible circuit board 1 is located on one side of the multiple battery cells 3. When the flexible circuit board 1 is mounted on the multiple sequentially spaced battery cells 3 through the nickel sheets 2, if the multiple battery cells 3 undergo periodic expansion-contraction deformation or are deformed by impact or tension, the nickel sheets 2 deform accordingly, simultaneously causing the flexible circuit board 1 to deform. Since the flexible circuit board 1 is flexible and elastic, the wavy bending portion 10 on the flexible circuit board 1 can deform and absorb the stress on the flexible circuit board 1, thereby effectively preventing the flexible circuit board 1 from breaking due to the expansion, impact, or tension of the battery cells 3. This effectively improves the reliability of the battery cell assembly. There is no need to etch a cantilever structure on the flexible circuit board 1, thus ensuring that the circuit board structure can cope with potential failures caused by external forces or fatigue of its own structure, while effectively simplifying the manufacturing process of the circuit board structure and reducing the manufacturing difficulty of the circuit board structure.

[0032] As can be seen, the bending portion 10 is a stretchable part between two adjacent nickel sheets 2 on the flexible circuit board 1. When the battery cell 3 expands, the bending portion 10 is stretched to counteract the stress generated by the expansion of the battery cell 3. When the battery cell 3 contracts, the bending portion 10 contracts back to its original shape. Thus, the circuit board structure provided in this embodiment of the invention can absorb the stress generated by the expansion and contraction of the battery cell 3 throughout the entire life cycle of the lithium battery through the stretching and contraction process of the bending portion 10, thereby preventing the circuit board structure from breaking and improving the reliability of the lithium-ion battery.

[0033] Compared to the etching process of the cantilever structure, the manufacturing process of the bending portion 10 is simpler. Therefore, the circuit board structure provided by the present invention can effectively simplify the manufacturing process of the circuit board structure and reduce the difficulty of the production process while improving the reliability of the circuit board structure.

[0034] It should also be noted that in the prior art, when soldering nickel sheets to both sides of a flexible printed circuit board, soldering errors can easily occur, leading to an increase in the initial stress of the flexible printed circuit board, thereby further increasing the failure risk of cantilever structure fracture on the flexible printed circuit board. This application eliminates the need for soldering the cantilever structure, not only avoiding the increased risk of cantilever structure fracture due to soldering nickel sheets, but also effectively absorbing the initial stress on the flexible circuit board 1 caused by nickel sheet soldering errors using the bending portion 10, thereby further improving the structural reliability of the circuit board structure provided in this embodiment of the invention.

[0035] Compared with the prior art, the circuit board structure provided by the embodiments of the present invention, through a plurality of bends 10 that increase sequentially from the middle to the end peaks 100 of the flexible circuit board 1, can fully absorb the stress generated on the flexible circuit board 1 due to the expansion and contraction of the battery cell 3, thereby preventing the flexible circuit board 1 from breaking. There is no need to etch cantilever structures on the circuit board, and there will be no phenomenon of over-etching of cantilever structures or incomplete etching of nickel sheet areas. It can improve the reliability of the circuit board structure while effectively simplifying the manufacturing process of the circuit board structure, reducing the difficulty of the production process, and improving production efficiency.

[0036] As shown in Figure 1, a plurality of bends 10 are provided between the middle part and any end of the flexible circuit board 1, and the maximum peak of the plurality of bends 10 on either side of the middle part of the flexible circuit board 1 increases sequentially from the middle part to the end of the flexible circuit board 1.

[0037] Since the maximum peak of the multiple bends 10 on either side of the middle of the flexible circuit board 1 increases sequentially from the middle to the end of the flexible circuit board 1, and when the battery cell 3 undergoes periodic expansion-contraction deformation, the degree of deformation on the multiple battery cells 3 increases from the middle battery cell 3 to the battery cells on both sides, the stress absorption capacity of the multiple bends 10 in the circuit board structure provided by the embodiment of the present invention can better adapt to the deformation of various parts of the flexible circuit board 1, thereby fully absorbing the stress at various parts of the flexible circuit board 1 and effectively improving the tensile and impact resistance of the circuit board structure.

[0038] Meanwhile, compared to using a bend 10 where all the wave peaks 100 are the same, the wave peaks 100 of the multiple bends 10 increase sequentially from the middle to the end of the flexible circuit board 1, which can maximize the stress absorption effect while effectively saving the material cost of the flexible circuit board 1 and reducing the material consumption of the circuit board structure provided in the embodiment of the present invention.

[0039] Furthermore, as shown in Figure 2, from one end of the flexible circuit board 1 to the other end, the troughs 101 of the multiple bends 10 on the flexible circuit board 1 are all equal, so that the surface of the flexible circuit board 1 at the troughs 101 of the multiple bends 10 are all located on the same horizontal plane.

[0040] As shown in Figure 2, the bend 10 between any two adjacent nickel sheets 2 has a peak 100.

[0041] Compared to the bending portion 10 between two adjacent nickel sheets 2, which has multiple peaks 100, a single peak 100 can simplify the bending degree of the bending portion 10 while satisfying the stress absorption of the bending portion 10, thereby simplifying the manufacturing process of the flexible circuit board 1.

[0042] As shown in Figure 1, multiple wavy bends 10 are connected in sequence, which makes the flexible circuit board bend continuously in an S-shape along its length, so that the entire flexible circuit board is wavy, and the peak of the wave gradually increases from the middle of the flexible circuit board to any end.

[0043] In one embodiment, as shown in Figures 1 and 2, the troughs 101 of two adjacent bends 10 are connected to each other to form a quadrilateral plate structure.

[0044] The quadrilateral structure at the connection of the troughs 101 of two adjacent bends 10 can be fixedly connected to the nickel sheet 2 by welding or other means. Thus, the quadrilateral structure at the connection of the troughs 101 of two adjacent bends 10 can provide a more stable and reliable connection point for the nickel sheet 2.

[0045] Meanwhile, the quadrilateral structure at the connection of the troughs 101 of two adjacent bends 10 can make the surface of the flexible circuit board 1 at the troughs 101 of the bends 10 flatter, thereby making the structure of the flexible circuit board 1 more stable.

[0046] Furthermore, when the connection point of the troughs 101 of two adjacent bends 10 is a quadrilateral structure, the bending process of the bends 10 can be effectively simplified, further reducing the manufacturing difficulty of the circuit board structure.

[0047] In one embodiment, as shown in Figures 1 and 2, the flexible circuit board 1 at the crest 100 of each bend 10 is a quadrilateral plate structure.

[0048] The flexible circuit board 1 at the crest 100 of the bending section 10 has a quadrilateral plate structure, which can make the structure of the flexible circuit board 1 more stable, and at the same time effectively simplify the bending process of the bending section 10, further reducing the manufacturing difficulty of the circuit board structure.

[0049] The quadrilateral plate-like structures at the troughs 101 of two adjacent bends 10, and the quadrilateral plate-like structures at the peaks 100 of the bends 10, can both be square or rectangular.

[0050] Furthermore, as shown in Figures 1 and 2, the flexible circuit board 1 between the crest 100 and the trough 101 of each bend 10 can be inclined, and from the side closer to the crest 100 to the side closer to the trough 101, the flexible circuit board 1 is inclined toward the direction closer to the bend 10 adjacent to it.

[0051] When the flexible circuit board 1 between the crest 100 and trough 101 of the bending portion 10 is tilted, it can not only further reduce the processing difficulty of the flexible circuit board 1, but also make the process of stress deformation absorbed by the bending portion 10 more stable, thereby improving the performance of the flexible circuit board 1.

[0052] As the expansion of the battery cell assembly gradually increases from the relative centerline in the middle towards both sides, the height of the bend 10 on the flexible circuit board 1 also increases from the relative centerline in the middle of the battery cell assembly towards both sides. Furthermore, since the width of the battery cell 3 is also greater for larger capacity cells, the length of the flexible circuit board 1 is also longer, which in turn leads to a longer length of the bend 10. In addition, the higher the design constraint of the lithium-ion battery module, the greater the preload of the battery cell 3 and the smaller the expansion of the battery cell 3, resulting in a smaller height of the bend 10. Therefore, the wave pitch and wave crest 100 of the bend 10 depend on the width and expansion of the battery cell 3, respectively.

[0053] Specifically, the wave pitch of the bending section 10 is determined only by the width of the battery cell 3 and the matching redundancy between the flexible circuit board 1 and the battery cell 3, as shown in Figure 2. The wave pitch of the bending section 10 is set as follows: The width of cell 3 is Then the wave pitch of the bent section 10 is It is calculated using the following formula (1): (1) Among them, To match the redundancy coefficient, a value of 1.05 to 1.2 is used. It is only used to compensate for the assembly gap between the flexible circuit board 1 and the battery cell 3, and is not affected by the battery cell expansion gradient.

[0054] The calculation process for the peaks 100 of each bend 10 is as follows: As shown in Figure 2, a center line is set at the middle position of multiple cells 3 (see the dotted line shown in Figure 2), and the horizontal coordinate of the center line is set. The x-coordinate of any point on the flexible circuit board 1 is ,but Where L is the total length of the flexible circuit board 1, and the two arrows shown in Figure 2 both indicate the expansion direction of the battery cell 3, with one arrow indicating the direction of expansion. Towards, the direction indicated by the other arrow is... Towards.

[0055] The bend 10 at the center line is set as the base bend 10. Then the peak of any bend 10 It is calculated using the following formula (2): (2) Among them, The wave height increment coefficient is used to characterize the incremental ratio of the edge wave height relative to the center wave height (i.e., the wave peak) of cell 3, and its value ranges from 0.1 to 0.4; the basic wave peak of the bend 10 at the center line. The longitudinal expansion at the center line of cell 3 is derived from the longitudinal expansion amount. Specifically, this longitudinal expansion amount can be obtained through a pre-tightening force test of cell 3 after multiple charge-discharge cycles.

[0056] Furthermore, the base peak of the bend 10 at the center line. It is calculated using the following formula (3): (3) Among them, This is a correction factor for the preload of the battery cell module, with a value ranging from 0.6 to 1.0. The greater the preload of the battery cell module, the better. The smaller; Let be the wave curvature coefficient of the bend 10. When the wave shape of the bend 10 is an arc, The value ranges from 0.5 to 0.8. When the wavy shape of the bend 10 is a broken line, The value ranges from 0.6 to 0.9.

[0057] Therefore, the wave pitch of the bending portion 10 above each cell 3 can be calculated using formula (1). By combining formula (1) and formula (2), the wave peak of the bending portion 10 above each cell 3 can be calculated. Once the wave peak and wave pitch of each bending portion 10 are calculated and set, a circuit board structure adapted to the current multiple cells 3 can be obtained through processes such as stamping or bending. In this way, the extensibility of each bending portion 10 can absorb the stress generated by the expansion and contraction of the cells throughout the entire life cycle, preventing the flexible circuit board 1 in the circuit board structure from breaking, thereby improving the reliability of the cell assembly and the lithium-ion battery.

[0058] It should be noted that, compared to the bends 10 where all the peaks 100 are equal, the peaks 100 at each bend 10 are calculated using formulas (2) and (3), so that the peaks 100 of the multiple bends 10 increase from the center of the flexible circuit board 1 to both ends. This not only improves the stress absorption effect of the multiple bends 10, but also minimizes the material cost of the flexible circuit board 1 and avoids material waste.

[0059] It can be seen that the embodiments of the present invention not only provide a plurality of bends 10 that increase from the middle to both ends of the flexible circuit board 1, but also provide a specific calculation method for the wave crests and the wave pitch, providing clearer guidance on how to process the flexible circuit board 1.

[0060] In one embodiment, the total wave pitch of each bend 10 is equal.

[0061] Compared to multiple bends 10 with different total wavelengths, multiple bends 10 with the same total wavelength not only simplify the processing of the flexible circuit board 1, but also help control the wave crest variables at each bend 10, thereby helping to control the stress absorption effect at each bend 10.

[0062] In one embodiment, the plate surfaces on both sides of any corner of the bend 10 are smoothly connected.

[0063] Compared to the sharp corners of the bend portion 10, the smooth transition connection method makes the corners of the bend portion 10 more rounded, thereby further simplifying the manufacturing process of the bend portion 10, improving the ease of processing and manufacturing of the circuit board structure provided in this embodiment of the invention, and improving the processing efficiency of the circuit board structure provided in this embodiment of the invention. In addition, the smooth transition connection method can also make the surface of the bend portion 10 smoother, which is beneficial to improving the stress absorption effect of the bend portion 10 and extending the service life of the bend portion 10.

[0064] In one embodiment, the number of bends 10 on one side of the middle portion of the flexible circuit board 1 is equal to the number of bends 10 on the other side of the middle portion of the flexible circuit board 1.

[0065] When the battery cell assembly composed of multiple battery cells 3 expands, the expansion amount gradually increases from the middle of the battery cell assembly to both sides, and the increase on both sides is roughly the same. Therefore, the number of bending portions 10 on both sides of the middle of the flexible circuit board 1 is equal. This not only further improves the processing convenience of the flexible circuit board 1, but also makes the stress absorption effect of the bending portions 10 on both sides of the middle of the flexible circuit board 1 more balanced, thereby improving the use effect of the circuit board structure provided by the embodiment of the present invention.

[0066] Furthermore, as shown in Figure 2, the bent portion 10 on one side of the middle of the flexible circuit board 1 and the bent portion 10 on the other side of the middle of the flexible circuit board 1 are symmetrically distributed with the center line of the flexible circuit board 1 as the axis of symmetry.

[0067] When the bent portions 10 on both sides of the middle of the flexible circuit board 1 are symmetrically distributed, the processing convenience of the flexible circuit board 1 can be further improved, and the stress absorption effect of the bent portions 10 on both sides of the middle of the flexible circuit board 1 can be further balanced, thereby further improving the use effect of the circuit board structure provided in the embodiment of the present invention.

[0068] It should be noted that, since the battery cell assembly provided in this embodiment of the invention includes the above-mentioned circuit board structure, the battery cell assembly provided in this embodiment of the invention can also fully absorb the stress generated on the flexible circuit board 1 due to the expansion and contraction of the battery cell 3 through multiple bends 10 that increase sequentially from the middle to the end peak 100 of the flexible circuit board 1, thereby preventing the flexible circuit board 1 from breaking. There is no need to etch a cantilever structure on the circuit board, and there will be no phenomenon of over-etching of the cantilever structure or incomplete etching of the nickel sheet area. While improving the reliability of the circuit board structure, it effectively simplifies the manufacturing process of the circuit board structure, reduces the difficulty of the production process, and improves the production efficiency.

[0069] This invention also provides a lithium-ion battery, which includes the aforementioned cell assembly. Therefore, this lithium-ion battery can also fully absorb the stress generated on the flexible circuit board 1 due to the expansion and contraction of the cell 3 through multiple bends 10 that increase sequentially from the middle to the end peaks 100, thereby preventing the flexible circuit board 1 from breaking. There is no need to etch cantilever structures on the circuit board, avoiding over-etching of the cantilever structure or incomplete etching of the nickel sheet area. This effectively simplifies the manufacturing process of the circuit board structure, reduces production difficulty, and improves production efficiency while enhancing the reliability of the circuit board structure.

[0070] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A circuit board structure, characterized in that, The circuit board structure includes a flexible circuit board (1) and a plurality of nickel sheets (2); the plurality of nickel sheets (2) are alternately distributed on both sides of the flexible circuit board (1) along the length direction of the flexible circuit board (1), and along the length direction of the flexible circuit board (1), the flexible circuit board (1) between any two adjacent nickel sheets (2) is provided with a wavy bending portion (10).

2. The circuit board structure according to claim 1, characterized in that, The flexible circuit board (1) is provided with a plurality of bending portions (10) from the middle to any end thereof, and the maximum peak of the plurality of bending portions (10) on either side of the middle of the flexible circuit board (1) increases sequentially from the middle to the end of the flexible circuit board (1).

3. The circuit board structure according to claim 1, characterized in that, From one end of the flexible circuit board (1) to the other end, the troughs (101) of the multiple bends (10) on the flexible circuit board (1) are all equal, so that the surfaces of the flexible circuit board (1) at the troughs (101) of the multiple bends (10) are all located on the same horizontal plane.

4. The circuit board structure according to claim 3, characterized in that, The bend (10) between any two adjacent nickel sheets (2) has a peak (100).

5. The circuit board structure according to any one of claims 1-4, characterized in that, The flexible circuit board (1) at the crest (100) of each of the aforementioned bends (10) has a quadrilateral plate-like structure.

6. The circuit board structure according to any one of claims 1-4, characterized in that, The plates on both sides of any corner of the bent portion (10) are smoothly connected.

7. The circuit board structure according to any one of claims 1-4, characterized in that, The number of bends (10) on one side of the middle of the flexible circuit board (1) is equal to the number of bends (10) on the other side of the middle of the flexible circuit board (1).

8. The circuit board structure according to claim 7, characterized in that, The bending portion (10) on one side of the middle of the flexible circuit board (1) and the bending portion (10) on the other side of the middle of the flexible circuit board (1) are symmetrically distributed with the center line of the flexible circuit board (1) as the axis of symmetry.

9. A battery cell assembly, characterized in that, The battery cell assembly includes the circuit board structure as described in any one of claims 1-8.

10. A lithium-ion battery, characterized in that, The lithium-ion battery includes the cell assembly as described in claim 9.

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