Battery protection plate and battery

Abstract

The utility model provides a kind of battery protection plate and battery, wherein, battery protection plate includes: PCB substrate;Line, setting in PCB substrate;Resistance piece, with line electrical connection, the end of resistance piece is attached with line arrangement, and resistance piece is integrally formed piece;Encapsulation layer, setting on PCB substrate, and encapsulation layer encapsulates line and resistance piece.The technical scheme of the application effectively solves the problem that the packaged battery protection plate is thicker in the related art.

Description

Technical Field

[0001] This utility model relates to the field of battery design technology, specifically to a battery protection board and a battery. Background Technology

[0002] Currently, there are high requirements for fast charging performance of batteries, which necessitates increasing the charging current. However, as the charging current increases, the temperature of the battery's PCB board also rises, potentially leading to overheating and compromising battery safety. Therefore, a battery protection board is needed to detect the charging current and limit it within a safe range.

[0003] In related technologies, a precision resistor structure is set on a PCB board to detect the current passing through the PCB. The precision resistor includes an alloy plate, electrodes, a substrate, and an insulating layer. The electrodes connect the alloy plate to the circuit, the substrate supports the alloy plate, and the insulating layer protects the alloy plate. To improve heat dissipation on the PCB board, an encapsulation layer is set on the surface of the PCB board, and this encapsulation layer encapsulates the precision resistor.

[0004] However, due to the relatively thick thickness of the precision resistors in the related technologies, the encapsulated battery protection board is also relatively thick, resulting in a relatively thick overall battery. Utility Model Content

[0005] The main purpose of this utility model is to provide a battery protection board and a battery to solve the problem of the excessive thickness of the encapsulated battery protection board in related technologies.

[0006] To achieve the above objectives, according to one aspect of the present invention, a battery protection board is provided, comprising: a PCB substrate; circuitry disposed on the PCB substrate; a resistor electrically connected to the circuitry, the end of the resistor being attached to the circuitry, and the resistor being an integrally formed component; and an encapsulation layer disposed on the PCB substrate, wherein the encapsulation layer encapsulates the circuitry and the resistor.

[0007] Furthermore, the resistive element is a metal wire, or the resistive element is a metal plate.

[0008] Furthermore, the circuit includes a first inner layer circuit disposed inside the PCB substrate and circuit pads disposed on the upper surface of the PCB substrate. The circuit pads are electrically connected to the first inner layer circuit. There are multiple circuit pads disposed at intervals. Resistors are connected between at least two circuit pads, and the ends of the resistors are attached to the circuit pads.

[0009] Furthermore, a solder resist ink layer is provided on the upper surface of the PCB substrate, and the solder resist ink layer surrounds the outside of the circuit pads. When the resistor is a metal plate, an avoidance notch is provided on the solder resist ink layer, and the avoidance notch is located between the PCB substrate and the resistor.

[0010] Furthermore, the circuit includes a second inner layer circuit disposed inside the PCB substrate. A groove is disposed on the PCB substrate, at least a portion of the second inner layer circuit is located on the bottom wall of the groove, at least a portion of the resistor is located inside the groove, and the end of the resistor is attached to the second inner layer circuit.

[0011] Furthermore, the distance between the upper surface of the resistor and the bottom surface of the sink is L1, and the distance between the PCB substrate and the bottom surface of the sink is L2, where L1≤L2.

[0012] Furthermore, the circuit also includes circuit pads disposed on the upper surface of the PCB substrate, and the battery protection board also includes bonding wires connecting the resistors and the circuit pads, and encapsulation layer encapsulation bonding wires.

[0013] Furthermore, the first end of the bonding wire is bonded to the resistor, and / or the second end of the bonding wire is bonded to the circuit pad.

[0014] Furthermore, the bottom wall of the settling tank is provided with a mounting cavity extending away from the resistor, and the second inner layer circuit is set in the mounting cavity, with the surface of the second inner layer circuit facing the resistor flush with the bottom wall of the settling tank.

[0015] According to another aspect of the present invention, a battery is provided, including a battery protection board, wherein the battery protection board is the aforementioned battery protection board.

[0016] The battery protection board of this utility model includes a PCB substrate, circuitry, resistors, and an encapsulation layer. The circuitry is disposed on the PCB substrate. The resistors are electrically connected to the circuitry, with their ends fitted into the circuitry. The resistors are integrally molded. The encapsulation layer is disposed on the PCB substrate and encapsulates both the circuitry and the resistors. This allows for the detection of current in the circuitry through the resistors. Because the resistors are integrally molded and their ends are fitted into the circuitry, the thickness of the resistors is reduced, as is the distance between the resistors and the PCB substrate, thus reducing the thickness of the encapsulated battery protection board. The encapsulation layer protects the circuitry and resistors, and its placement on the PCB substrate facilitates heat conduction between the PCB substrate and the resistors, resulting in more even heat distribution, reducing the possibility of localized overheating, and improving battery safety. Therefore, the technical solution of this application effectively solves the problem of excessively thick encapsulated battery protection boards in related technologies. Attached Figure Description

[0017] The accompanying drawings, which form part of this application, are used to provide a further understanding of the present invention. The illustrative embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an undue limitation of the present invention. In the drawings:

[0018] Figure 1 A side perspective view of a first embodiment of the battery protection board according to the present invention is shown.

[0019] Figure 2 It shows Figure 1 A side perspective view of Embodiment 2 of the battery protection board;

[0020] Figure 3 It shows Figure 1 A side perspective view of Embodiment 3 of the battery protection board;

[0021] Figure 4 It shows Figure 1 A side perspective view of Embodiment 4 of the battery protection board.

[0022] The above figures include the following reference numerals:

[0023] 10. PCB substrate; 11. Recessed tank;

[0024] 21. Metal wire; 22. Metal plate;

[0025] 31. Circuit pads; 32. Second inner layer circuitry;

[0026] 40. Encapsulation layer;

[0027] 51. Solder resist ink layer; 52. Bonding line. 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, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present utility model or its application or use. All other embodiments obtained by those skilled in the art based on the embodiments of the present utility model without creative effort are within the scope of protection of the present utility model.

[0029] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0030] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps described in these embodiments do not limit the scope of this invention. It should also be understood that, for ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters in the following drawings denote similar items; therefore, once an item is defined in one drawing, it need not be further discussed in subsequent drawings.

[0031] In this embodiment, the battery protection board includes: a PCB substrate 10, circuitry, resistors, and an encapsulation layer 40. The circuitry is disposed on the PCB substrate 10. The resistors are electrically connected to the circuitry, and the ends of the resistors are fitted into the circuitry. The resistors are integrally molded. The encapsulation layer 40 is disposed on the PCB substrate 10 and encapsulates the circuitry and resistors.

[0032] In this way, the current in the circuit can be detected by setting a resistor. Since the resistor is a one-piece molded component and its end is fitted to the circuit, the thickness of the resistor is small, and the distance between the resistor and the PCB substrate 10 is reduced, thereby reducing the thickness of the encapsulated battery protection board. The encapsulation layer 40 protects the circuit and the resistor, and since it is located on the PCB substrate 10, it can conduct heat between the PCB substrate 10 and the resistor, resulting in more even heat distribution, reducing the possibility of localized overheating, and improving battery safety. Therefore, the technical solution of this application effectively solves the problem of the excessive thickness of the encapsulated battery protection board in related technologies. Furthermore, a thinner battery protection board also reduces the overall weight of the battery, improving product competitiveness.

[0033] It should be noted that a unibody component refers to a manufactured product in which multiple parts or components are integrated into a single unit through a single processing or molding process. The core of this process lies in reducing the number of parts, the size of parts, and the assembly steps, thereby improving efficiency and reducing costs. Therefore, by making the resistor a unibody component, the thickness of the resistor can be reduced, thereby reducing the distance between the resistor and the PCB substrate 10, and thus reducing the thickness of the packaged battery protection board.

[0034] like Figure 1As shown, in Embodiment 1, the resistive element is a metal wire 21. When the resistive element is in the form of a metal wire 21, the slender structure of the metal wire 21 can further reduce the volume and thickness it occupies. Compared with the packaging form of precision resistors in related technologies, the setting of the metal wire 21 can significantly reduce the overall thickness of the battery protection board. At the same time, the high thermal conductivity of the metal wire 21 helps the heat dissipate quickly. Multiple metal wires 21 are arranged in parallel.

[0035] The difference between Embodiment 1 and Embodiment 2 is that the form of the resistor in Embodiment 2 is different from that in Embodiment 1.

[0036] like Figure 2 As shown, in Embodiment 2, the resistor is a metal plate 22. Using a metal plate 22 as the resistor improves the mechanical stability of the resistor, makes the connection between the resistor and the PCB board more reliable, improves heat conduction efficiency, enhances current carrying capacity, and simplifies the manufacturing process.

[0037] like Figure 1 and Figure 2 As shown in Embodiments 1 and 2, the circuitry includes a first inner layer circuitry disposed inside the PCB substrate 10 and circuit pads 31 disposed on the upper surface of the PCB substrate 10. The circuit pads 31 are electrically connected to the first inner layer circuitry. Two circuit pads 31 are spaced apart, and a resistor is connected between the two circuit pads 31, with the end of the resistor being attached to the circuit pad 31. By configuring the first inner layer circuitry and electrically connecting the circuit pads 31 on the upper surface of the PCB substrate 10 to the first inner layer circuitry, the resistor can be directly attached to the circuit pads 31 and thus electrically connected to the circuitry. This simplifies the manufacturing process, improves production efficiency, and enhances the accuracy and reliability of current detection.

[0038] In Embodiment 1 and Embodiment 2, a detection chip for detecting current is provided on the first inner layer circuit.

[0039] The inventors discovered that in related technologies, the precision resistor and the circuit pad 31 are connected by reflow soldering, requiring a solder paste layer between the precision resistor and the circuit pad 31. Because the solder paste contains many impurities, it affects the accuracy of current detection, especially at higher currents. However, by applying the technical solutions of Embodiments 1 and 2, the end of the resistor is fitted into the circuit pad 31, avoiding the introduction of a solder paste layer and reducing impurities between the resistor and the circuit pad 31, thereby improving the accuracy of current detection.

[0040] In other embodiments, the line pads 31 are three, four or more spaced apart, and the resistors are connected between the three, four or more line pads 31.

[0041] like Figure 2 As shown, in Embodiment 2, a solder resist layer 51 is provided on the upper surface of the PCB substrate 10, surrounding the outer side of the circuit pads 31. When the resistor is a metal plate 22, a clearance notch is provided on the solder resist layer 51, located between the PCB substrate 10 and the resistor. The solder resist layer 51 on the upper surface of the PCB substrate 10 can effectively prevent solder flow in non-circuit pad areas, avoiding faults such as short circuits. For resistors in the form of metal plates 22, the clearance notch on the solder resist layer 51 reduces the possibility of the metal plate 22 being lifted by the solder resist layer 51, allowing the metal plate 22 to better and more tightly adhere to the circuit pads 31, improving the stability of the electrical connection between the metal plate 22 and the circuit pads 31.

[0042] It should be noted that the solder resist ink layer 51 surrounding the outside of the circuit pad 31 means that the solder resist ink layer 51 is located on the side of the outer peripheral sidewall of the circuit pad 31 away from the center of the circuit pad 31.

[0043] The difference between Embodiment 3 and Embodiment 4 and Embodiment 1 is that a recessed groove 11 is provided on the PCB substrate 10 in Embodiment 3 and Embodiment 4, and the resistor is disposed in the recessed groove 11.

[0044] like Figure 3 and Figure 4 As shown, in Embodiments 3 and 4, the circuitry includes a second inner layer circuitry 32 disposed within the PCB substrate 10. A recessed groove 11 is provided on the PCB substrate 10, and at least a portion of the second inner layer circuitry 32 is located on the bottom wall of the recessed groove 11. At least a portion of the resistor is located within the recessed groove 11, with its end in contact with the second inner layer circuitry 32. By providing a recessed groove 11 on the PCB substrate 10 and designing at least a portion of the second inner layer circuitry 32 on the bottom wall of the recessed groove 11, direct contact between the resistor and the second inner layer circuitry 32 can be achieved, further reducing the height of the resistor protruding from the upper surface of the PCB substrate 10 and further reducing the thickness of the battery protection board. In Embodiments 3 and 4, there is an installation gap between the resistor and the side wall of the recessed groove 11.

[0045] like Figure 3 and Figure 4As shown, in Embodiments 3 and 4, the distance between the upper surface of the resistor and the bottom surface of the sink 11 is L1, and the distance between the PCB substrate 10 and the bottom surface of the sink 11 is L2, where L1 ≤ L2. This allows the upper surface of the resistor to be lower than or flush with the upper surface of the PCB substrate 10, further reducing the height of the resistor protruding from the upper surface of the PCB substrate 10 and avoiding assembly problems and mechanical damage risks caused by the resistor protruding from the PCB substrate 10. Simultaneously, this design also facilitates uniform coverage of the encapsulation layer 40, optimizing the overall encapsulation effect of the battery.

[0046] The difference between Embodiment 3 and Embodiment 4 is that in Embodiment 4, a bonding wire 52 is used to connect the resistor and the circuit pad 31.

[0047] like Figure 4 As shown, in Embodiment 4, the circuit also includes circuit pads 31 disposed on the upper surface of the PCB substrate 10. The battery protection board also includes bonding wires 52 connecting the resistor and the circuit pads 31, and the encapsulation layer 40 encapsulates the bonding wires 52. Introducing the bonding wires 52 to connect the resistor and the circuit pads 31 not only provides a more flexible connection method to adapt to different layout requirements, but also allows the use of the bonding wires 52 to be unrestricted by the routing of the PCB substrate 10, reducing the complexity of the circuit design. The bonding of the bonding wires 52 with the circuit pads 31 and the resistor, and the encapsulation of the bonding wires 52 by the encapsulation layer 40, ensure the stability of the connection and the reliability of the electrical performance, while also protecting the bonding wires 52 from external environmental influences, improving the structural stability and electrical safety performance of the battery protection board.

[0048] In embodiment four, the resistor is connected to the circuit pad 31 via the bonding wire 52. The circuit pad 31 is electrically connected to the first inner layer circuit inside the PCB substrate 10. A detection chip for detecting current is connected to the first inner layer circuit.

[0049] The inventors discovered that in related technologies, using copper foil to connect the resistor and the circuit pad 31 can affect the accuracy of current detection due to impurities within the copper foil. However, the technical solution of Embodiment 4, through the inclusion of the bonding wire 52, reduces the introduction of impurities and improves the accuracy of current detection.

[0050] like Figure 4As shown, in Embodiment 4, the first end of the bonding wire 52 is bonded to the resistor, and / or the second end of the bonding wire 52 is bonded to the circuit pad 31. When the first end of the bonding wire 52 is bonded to the resistor and the second end is bonded to the circuit pad 31, this connection method ensures efficient current transmission between the bonding wire 52 and the resistor and circuit pad 31, reduces contact resistance and signal loss, and improves the accuracy of current detection and the reliability of electrical connections. At the same time, the stability of the bonded connection also helps to reduce connection loosening and performance degradation caused by vibration and temperature changes, improving the long-term stability and safety of the battery protection board.

[0051] like Figure 3 and Figure 4 As shown in Embodiments 3 and 4, a mounting cavity extending away from the resistor is provided on the bottom wall of the sink 11. The second inner layer circuit 32 is disposed within the mounting cavity, and the surface of the second inner layer circuit 32 facing the resistor is flush with the bottom wall of the sink 11. This reduces the height occupied by the second inner layer circuit 32 within the sink 11, facilitating the processing of the sink 11 and allowing the resistor to fully utilize the height of the sink 11, further reducing the height of the resistor protruding from the upper surface of the PCB substrate 10.

[0052] Furthermore, the resistor and the circuit are connected by one of the following methods: high-temperature ultrasonic welding, thermocompression welding, or crimping. These methods not only ensure a reliable connection between the resistor and the circuit, but also, compared to reflow soldering and other welding processes in related technologies, reduce solder usage, minimize the introduction of impurities, and lower the connection height, thus helping to further reduce the thickness of the battery protection board.

[0053] This application also provides a battery including a battery protection board, which is the aforementioned battery protection board. Because the aforementioned battery protection board can solve the problem of excessive thickness of the encapsulated battery protection board in related technologies, the battery having this battery protection board can solve the same technical problem.

[0054] The inventors discovered that in related technologies, the PCB board thickness is 0.7mm, the circuit pad 31 thickness is 0.1mm, the solder paste thickness is 0.12mm, the alloy plate thickness of the precision resistor is 0.4mm, the insulating layer thickness of the precision resistor is 0.1mm, and the insulating layer covering the alloy plate is 0.75mm. Thus, the overall thickness of the battery protection board is 1.45mm. However, by applying the technical solution of Embodiment 2 of this application, the thickness of the solder paste and the insulating layer are reduced, resulting in an overall battery protection board thickness of 1.13mm. The thickness of the battery protection board in Embodiment 2 of this application is reduced by 22.1% compared to the battery protection board in related technologies. Applying the technical solution of Embodiment 1 of this application, the PCB substrate 10 thickness is 0.7mm, the encapsulation layer 40 thickness is 0.23mm, and the battery protection board thickness is 0.93mm. Thus, the thickness of the battery protection board in Embodiment 1 of this application is reduced by 35.9% compared to the battery protection board in related technologies.

[0055] In the description of this utility model, it should be understood that the directional terms such as "front, back, up, down, left, right", "horizontal, vertical, horizontal" and "top, bottom" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description. Unless otherwise stated, these directional terms do not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the scope of protection of this utility model. The directional terms "inner" and "outer" refer to the inner and outer contours of each component itself.

[0056] For ease of description, spatial relative terms such as "above," "on top of," "on the upper surface of," "above," etc., are used herein to describe the spatial positional relationship of a device or feature as shown in the figures to other devices or features. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation beyond the orientation of the device as described in the figures. For example, if the device in the figures were inverted, a device described as "above" or "on top of" other devices or structures would subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein will be interpreted accordingly.

[0057] Furthermore, it should be noted that the use of terms such as "first" and "second" to define components is merely for the purpose of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore cannot be construed as limiting the scope of protection of this utility model.

[0058] The above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A battery protection board, characterized in that, include: PCB substrate(10); The circuit is disposed on the PCB substrate (10); A resistor is electrically connected to the circuit, with its end fitting against the circuit, and the resistor is a one-piece molded component. An encapsulation layer (40) is disposed on the PCB substrate (10), and the encapsulation layer (40) encapsulates the circuit and the resistor.

2. The battery protection board according to claim 1, characterized in that, The resistive element is a metal wire (21), or the resistive element is a metal plate (22).

3. The battery protection board according to claim 1 or 2, characterized in that, The circuit includes a first inner layer circuit disposed inside the PCB substrate (10) and a circuit pad (31) disposed on the upper surface of the PCB substrate (10). The circuit pad (31) is electrically connected to the first inner layer circuit. There are multiple circuit pads (31) spaced apart. The resistor is connected between at least two of the circuit pads (31). The end of the resistor is attached to the circuit pad (31).

4. The battery protection board according to claim 3, characterized in that, The upper surface of the PCB substrate (10) is provided with a solder resist ink layer (51), which surrounds the outside of the circuit pad (31). When the resistor is a metal plate (22), the solder resist ink layer (51) is provided with a clearance notch, which is located between the PCB substrate (10) and the resistor.

5. The battery protection board according to claim 1 or 2, characterized in that, The circuit includes a second inner layer circuit (32) disposed inside the PCB substrate (10). A groove (11) is disposed on the PCB substrate (10). At least a portion of the second inner layer circuit (32) is located on the bottom wall of the groove (11). At least a portion of the resistor is located inside the groove (11). The end of the resistor is attached to the second inner layer circuit (32).

6. The battery protection board according to claim 5, characterized in that, The distance between the upper surface of the resistor and the bottom surface of the sink (11) is L1, and the distance between the PCB substrate (10) and the bottom surface of the sink (11) is L2, where L1≤L2.

7. The battery protection board according to claim 5, characterized in that, The circuit also includes a circuit pad (31) disposed on the upper surface of the PCB substrate (10), and the battery protection board also includes a bonding line (52) connecting the resistor and the circuit pad (31), and the encapsulation layer (40) encapsulates the bonding line (52).

8. The battery protection board according to claim 7, characterized in that, The first end of the bonding wire (52) is attached to the resistor, and / or the second end of the bonding wire (52) is attached to the line pad (31).

9. The battery protection board according to claim 5, characterized in that, The bottom wall of the sink (11) is provided with a mounting cavity extending away from the resistor. The second inner layer circuit (32) is disposed in the mounting cavity, and the surface of the second inner layer circuit (32) facing the resistor is flush with the bottom wall of the sink (11).

10. A battery, comprising a battery protection board, characterized in that, The battery protection board is the battery protection board according to any one of claims 1 to 9.

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