Welding piece, protection plate assembly and battery

Abstract

The utility model relates to the field of battery structures, in particular to a welding piece, a protection plate assembly and a battery. The welding piece is used for connecting a conductive plate of a battery cell and a circuit board, and comprises a first connecting part and a second connecting part; one side of the first connecting part in the thickness direction is connected with the conductive plate; the second connecting part is provided with a connecting surface which is connected with the circuit board; the first connecting part is connected with the second connecting part, and a height difference exists between the other side of the first connecting part in the thickness direction and the connecting surface of the second connecting part, so that a reserved gap is formed between the first connecting part and the circuit board. According to the welding piece provided by the invention, the welding spot cannot be in contact with the PCB, so that the welding spot cannot penetrate into the PCB to cause short circuit of an internal circuit of the PCB; and the reserved gap can physically isolate the welding spot from the PCB, so that the transmission of welding energy is reduced, the control requirement of the welding energy is reduced, and the performance of the PCB is prevented from being damaged by the welding energy.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of battery structure, in particular to a welding sheet, a protection plate assembly and a battery. BACKGROUND

[0002] In the existing battery pack packaging scheme, the connection between the circuit board and the cell tab or adapter sheet usually adopts a flat contact sheet, and the entire back surface of the flat contact sheet is in contact with the PCB (Printed Circuit Board). This design is simple in structure, but some problems are faced in the actual production process.

[0003] Specifically, in the process of welding the flat contact sheet with the cell tab or adapter sheet, the fluctuation of welding energy will cause the instability of welding penetration. When the welding energy is too high, the welding point may exceed the thickness of the welding sheet, and then penetrate the circuit board, causing short circuit inside the circuit board and other problems. Such risks not only affect the performance of the battery pack, but also may cause fire or explosion and other safety hazards. Therefore, how to ensure the safety of the circuit board while ensuring the welding quality has become a problem to be solved in the manufacturing process of the battery pack. UTILITY MODEL CONTENT

[0004] The purpose of the present application is to provide a welding sheet, a protection plate assembly and a battery, which are used to solve the problem of short circuit inside the circuit board caused by the penetration of the welding point into the circuit board.

[0005] The present application provides a welding sheet for connecting a conductive plate of a cell and a circuit board, the welding sheet comprising a first connecting part and a second connecting part;

[0006] One side of the first connecting part in the thickness direction thereof is connected with the conductive plate;

[0007] The second connecting part is provided with a connecting surface, and the connecting surface is connected with the circuit board;

[0008] The first connecting part is connected with the second connecting part, and the first connecting part has a height difference between the other side thereof in the thickness direction thereof and the connecting surface of the second connecting part, so as to form a reserved gap between the first connecting part and the circuit board.

[0009] In the above technical solution, further, the first connecting part is a first connecting plate formed by arching a part of the welding sheet towards the conductive plate, and the plate surface of the first connecting plate is connected with the conductive plate;

[0010] The second connecting part is a second connecting plate formed by the rest of the welding sheet, and the plate surface of the second connecting plate is connected with the circuit board.

[0011] In the technical scheme, further, the first connecting plate is located at the middle part of the welding sheet, and the second connecting plate is located at the circumference of the first connecting plate.

[0012] In the technical scheme, further, the number of the second connecting plates is multiple, and the multiple second connecting plates are arranged at intervals and surround the circumference of the first connecting plate.

[0013] In the technical scheme, further, the distance between the conductive plate and the circuit board is H, the thickness of the first connecting part is d, and the height difference is h, and h=H-d.

[0014] In the technical scheme, further, the connecting surface is provided with a copper plating layer.

[0015] The application further provides a protection plate assembly comprising a circuit board and the welding sheet.

[0016] In the technical scheme, further, the circuit board is provided with a welding sheet pad, and the welding sheet pad is matched with the connecting surface.

[0017] In the technical scheme, further, the circuit board is provided with the adhesive layer, and the adhesive layer is used for connecting the top of the battery cell.

[0018] The application further provides a battery comprising a battery cell and the protection plate assembly.

[0019] Compared with the prior art, the application has the following beneficial effects:

[0020] The welding sheet provided by the application forms a reserved gap between the first connecting part and the PCB board, so that the welding point cannot contact the PCB board, and the welding point cannot pierce into the PCB board to cause short circuit of the internal circuit of the PCB board, thereby achieving a safety effect. The reserved gap can physically isolate the welding point and the PCB board, reduce the transmission of welding energy, reduce the control requirement of welding energy, avoid damage to the performance of the PCB board caused by welding energy, reduce the safety risk, and improve the overall reliability.

[0021] The application further provides a protection plate assembly comprising a circuit board and the welding sheet. Based on the above analysis, the battery also has the above beneficial effects, which will not be described here.

[0022] The application further provides a battery comprising a battery cell and the protection plate assembly. Based on the above analysis, the battery also has the above beneficial effects, which will not be described here. BRIEF DESCRIPTION OF DRAWINGS

[0023] In order to more clearly illustrate the technical solutions in the specific embodiments or prior art of the present application, the drawings needed to be used in the description of the specific embodiments or prior art will be briefly introduced. Obviously, the drawings in the following description are some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0024] Figure 1 The first structural schematic diagram of the welding sheet provided by the present application;

[0025] Figure 2 The second structural schematic diagram of the welding sheet provided by the present application;

[0026] Figure 3 The third structural schematic diagram of the welding sheet provided by the present application;

[0027] Figure 4 The structural schematic diagram of the protection plate assembly provided by the present application;

[0028] Figure 5 The partial structural schematic diagram of the protection plate assembly provided by the present application.

[0029] In the figure: 1-welding sheet; 101-first connecting part; 102-second connecting part; 103-reserved gap; 104-welding spot; 2-welding sheet pad; 3-lead wire NTC; 4-PCB board; 5-terminal wire; 6-electric core; 7-electric core tab; 8-adhesive layer. DETAILED DESCRIPTION

[0030] The technical solutions of the present application will be described clearly and completely in combination with the drawings. Obviously, the described embodiments are some embodiments of the present application, not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0031] In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" and the like indicate the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first", "second", "third" are only for the purpose of description, and cannot be understood as indicating or implying relative importance.

[0032] In the description of the present application, it should be noted that unless otherwise explicitly specified and limited, the terms "mounting", "connection", "connecting" should be understood in a broad sense, for example, can be fixedly connected, or can be detachably connected, or integrally connected; can be mechanically connected, or can be electrically connected; can be directly connected, or can be indirectly connected through an intermediate medium, or can be internal communication of two elements. For those skilled in the art, the specific meanings of the above terms in the present application can be understood according to the specific circumstances.

[0033] Embodiment one

[0034] Referring to Figures 1 to 5 As shown in the drawings, the welding sheet 1 provided by the present application is located between the conductive plate of the battery cell 6 and the circuit board, and the conductive plate is specifically the battery cell tab 7 (hereinafter, the battery cell tab 7 is taken as an example for description) or the adapter sheet, and the circuit board is specifically the PCB 4. When connecting the battery cell tab 7 and the PCB 4, generally, spot welding of the welding sheet 1 is performed on the PCB 4, and the battery cell tab 7 can be spot welded on the welding sheet 1.

[0035] When the battery cell tab 7 and the existing welding sheet 1 are laser spot welded, since the welding sheet 1 is completely attached to the PCB 4, when the welding spot 104 exceeds the thickness of the welding sheet 1, there is a risk of breaking through the PCB 4, causing internal short circuit and other safety risks of the PCB 4, and the welding laser energy is easy to cause damage to the PCB 4.

[0036] In order to solve the above problems, the welding sheet 1 provided by the present application includes a first connecting part 101 and a second connecting part 102; the first connecting part 101 is connected with the battery cell tab 7 on one side in the thickness direction of the first connecting part 101; the second connecting part 102 is provided with a connecting surface, and the connecting surface is connected with the PCB 4; the first connecting part 101 is connected with the second connecting part 102, and the first connecting part 101 has a height difference between the other side in the thickness direction of the first connecting part 101 and the connecting surface of the second connecting part 102, so as to form a reserved gap 103 between the first connecting part 101 and the PCB 4.

[0037] Specifically, when welding the welding sheet 1 with the cell tab 7 and the PCB 4, the connecting surface of the second connecting part 102 is welded with the PCB 4, and the cell tab 7 is welded with one side of the first connecting part 101 in the thickness direction. At this time, a raised welding spot 104 is formed on the other side of the first connecting part 101 in the thickness direction. Since there is a height difference between this side of the first connecting part 101 and the connecting surface of the second connecting part 102, a reserved gap 103 is formed between the first connecting part 101 and the PCB 4, and the generated welding spot 104 cannot contact the PCB 4, so that the welding spot 104 cannot pierce into the PCB 4 to cause short circuit of the internal circuit of the PCB 4, achieving a safety effect; and the reserved gap 103 can physically isolate the welding spot 104 from the PCB 4, reduce the transmission of welding energy, so that the control requirement of welding energy is reduced, avoiding damage to the performance of the PCB 4 by welding energy, reducing the safety risk, and improving the overall reliability.

[0038] In the prior art, the material of the side of the flat contact sheet facing the PCB 4 is a nickel sheet, and the stability during welding is poor. In the optional scheme of this embodiment, the connecting surface of the second connecting part 102 is provided with a copper plating layer, which can improve the welding stability and increase the weldability of the welding sheet 1.

[0039] In the optional scheme of this embodiment, the first connecting part 101 is a first connecting plate formed by arching the local part of the welding sheet towards the cell tab 7, and the plate surface of the first connecting plate is connected with the cell tab 7; and the second connecting part 102 is a second connecting plate corresponding to the remaining part of the welding sheet, and the plate surface of the second connecting plate is connected with the PCB 4.

[0040] In this embodiment, the plate surface of the first connecting plate is connected with the cell tab 7, so that the first connecting plate is connected with the cell tab 7 in a better fit and with a larger contact area, avoiding virtual connection between the two to affect the conductivity. Similarly, the plate surface of the second connecting plate is connected with the PCB 4, so that the second connecting plate is connected with the PCB 4 in a better fit and with a larger contact area, avoiding virtual connection between the two to affect the conductivity. In addition, the first connecting part 101 and the second connecting part 102 are both plate-shaped structures, which can also reduce the use of consumables, reduce the cost and weight.

[0041] In the optional scheme of this embodiment, the first connecting plate is located at the middle of the welding sheet 1, and the second connecting plate is located at the circumference of the first connecting plate. Further, the number of the second connecting plates is multiple, and the multiple second connecting plates are arranged at intervals and surround the circumference of the first connecting plate.

[0042] In this embodiment, as Figures 1 to 3As shown, the first connecting plate and the second connecting plate are integrally bent into shape. The first connecting plate is located in the middle of the welding piece 1 and arches towards the battery cell tab 7. Multiple second connecting plates surround the first connecting plate around its circumference and arch towards the PCB board 4. It should be noted that the arch height, shape, bending angle, and number of the second connecting plates are not limited to the structure shown in the figure and can be set according to actual needs.

[0043] In actual production, when welding the battery cell tab 7 to the first connecting part 101, the pressure claws of the welding equipment apply pressure from the side of the battery cell tab 7. The middle part of the welding piece 1 arches up to form the first connecting plate, which can provide support on the other side of the battery cell tab 7, preventing the pressure claws from damaging the battery cell tab 7 and affecting the welding effect. Multiple second connecting plates are arranged at intervals and surround the circumference of the first connecting plate. Compared with the integral structure of the second connecting part, the segmented structure of multiple second connecting plates makes the welding piece less likely to be damaged when the equipment applies pressure and bends it. The multiple second connecting plates form a multi-claw arched design, which can provide a certain degree of support in the circumference.

[0044] In the optional scheme of this embodiment, the first connecting plate and the second connecting plate can be configured as the structure shown in the figure, or as an "I" shape, "Z" shape, etc. However, compared with the structure shown in the figure, the above structures are more difficult to process and have lower stability.

[0045] Example 2

[0046] The welding piece in this second embodiment is an improvement based on the above embodiments. The technical content disclosed in the above embodiments will not be described again, and the content disclosed in the above embodiments also belongs to the content disclosed in this second embodiment.

[0047] In this embodiment, the distance between the battery cell tab 7 and the PCB board 4 is H, the thickness of the first connection part 101 is d, the height difference is h, and h = Hd.

[0048] In this embodiment, because the base of the battery tab 7 is capped, the PCB board 4 needs to be connected to the cap when it is installed and fixed. When the battery tab 7 is led out, the presence of the cap creates a gap between the battery tab 7 and the PCB board 4. When soldering the battery tab 7 to the PCB board 4, the existing flat contact plate is too thin to fill this gap, resulting in a height difference between the battery tab 7 and the flat contact plate. The battery tab 7 needs to be bent and shaped before it can be soldered to the flat contact plate. However, the arched structure formed by the welding piece 1 provided in this application can fill the gap between the battery tab 7 and the PCB board 4, so that the battery tab 7 can be soldered to the welding piece 1 without bending and shaping, which can reduce processing steps and improve production efficiency.

[0049] Example 3

[0050] The embodiment three of the present application provides a protection plate assembly, which comprises a PCB and the soldering sheet of any one of the above embodiments, so that the protection plate assembly has all the beneficial technical effects of the soldering sheet of any one of the above embodiments, which will not be repeated here.

[0051] In the optional scheme of the embodiment, the PCB 4 is provided with the soldering sheet pad 2, and the soldering sheet pad 2 is matched with the connecting surface.

[0052] In the embodiment, as shown in Figure 1 , Figure 2 and Figure 4 , the first connecting plate and the second connecting plate are both rectangular. The number of the second connecting plates is six, of which two second connecting plates are arranged on the long side of the first connecting plate, and one second connecting plate is arranged on the short side of the first connecting plate. Six soldering sheet pads 2 are also arranged on the PCB 4, and the soldering surface of the soldering sheet pad 2 is matched with the plate surface of the second connecting plate, so as to be soldered with the six second connecting plates one by one.

[0053] In addition, the first connecting plate can also be square, circular, elliptical or other structures. For the square first connecting plate, the second connecting plate can be rectangular, and the same number of second connecting plates are arranged at the four sides of the first connecting plate. For the circular and elliptical first connecting plates, the second connecting plates can be correspondingly arranged in an arc shape, and the number can be set according to the actual situation. It is only necessary to ensure that the soldering sheet pads 2 arranged on the PCB 4 are matched with the second connecting plates.

[0054] In the optional scheme of the embodiment, as shown in Figure 3 , the protection plate assembly further comprises a glue layer 8. The glue layer 8 is arranged on the PCB 4, and is used to connect the top of the battery cell 6, so as to realize the installation and fixation of the PCB 4.

[0055] In the optional scheme of the embodiment, as shown in Figure 4 , the protection plate assembly further comprises a lead NTC 3 and a terminal wire 5, and the lead NTC 3 and the terminal wire 5 are arranged on the PCB 4.

[0056] Embodiment four

[0057] The embodiment four of the present application provides a battery, which comprises a battery cell and the protection plate assembly of the above embodiment three, so that the battery has all the beneficial technical effects of the protection plate assembly of the above embodiment, which will not be repeated here.

[0058] It should be noted that the above-mentioned embodiments are only used to illustrate but not to limit the technical solutions of the present application; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that they can still make modifications to the technical solutions recorded in the foregoing embodiments, or make equivalent replacements to some or all of the technical features; and these modifications or replacements 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 application. In addition, those skilled in the art can understand that the combination of features of different embodiments means that it is within the scope of the present application and forms different embodiments, although some embodiments include certain features rather than other features included in other embodiments.

Claims

1. A solder tab for connecting a conductive plate member of a battery cell to a circuit board, characterized by, The welding piece comprises a first connecting part and a second connecting part; One side of the first connecting part in the thickness direction thereof is connected with the conductive plate member; The second connecting part is provided with a connecting surface connected with the circuit board; The first connecting part is connected with the second connecting part, and the first connecting part has a height difference between the other side thereof in the thickness direction and the connecting surface of the second connecting part, so that a reserved gap is formed between the first connecting part and the circuit board.

2. The welding tip according to claim 1, wherein The first connecting part is a first connecting plate formed by arching a local part of the welding piece towards the conductive plate member, and the plate surface of the first connecting plate is connected with the conductive plate member; The second connecting part is a second connecting plate formed by the rest part of the welding piece, and the plate surface of the second connecting plate is connected with the circuit board.

3. The welding tip of claim 2, wherein The first connecting plate is located in the middle of the welding piece, and the second connecting plate is located in the circumferential direction of the first connecting plate.

4. The solder sheet according to claim 3, characterized in that The number of the second connecting plates is multiple, and the multiple second connecting plates are arranged in intervals and surround the circumferential direction of the first connecting plate.

5. The solder tab of claim 1, wherein, The distance between the conductive plate member and the circuit board is H, the thickness of the first connecting part is d, the height difference is h, and h=H-d.

6. The solder sheet according to claim 1, characterized by The connecting surface is provided with a copper plating layer.

7. A protective panel assembly characterized by, The circuit board and the welding piece as claimed in any one of claims 1 to 6 are comprised.

8. The protective panel assembly of claim 7, wherein, The circuit board is provided with a welding piece pad, and the welding piece pad is matched with the connecting surface.

9. The protective panel assembly of claim 7, wherein, A glue layer is further comprised, and the glue layer is arranged on the circuit board and used for connecting the top of the battery cell.

10. A battery, characterized by The battery cell and the protection plate assembly as claimed in any one of claims 7 to 9 are comprised.

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