Circuit board assembly and battery

Abstract

The utility model relates to the technical field of circuit boards, and discloses a circuit board assembly and a battery, and the circuit board assembly comprises a printed circuit board which is provided with a conductive area; the heat conduction hard shell is connected with the printed circuit board and is provided with a mounting cavity, and the printed circuit board covers the mounting cavity; and the component is mounted in the mounting cavity and is connected with the conductive region. According to the circuit board assembly provided by the utility model, the components are installed on the printed circuit board through the heat conduction hard shell, so that the assembly stress borne by the components can be reduced, the heat dissipation efficiency of the components is improved, and the thermal stress borne by the components is reduced.

Description

TECHNICAL FIELD

[0001] The utility model relates to circuit board technical field, concretely relates to a circuit board assembly and battery. BACKGROUND

[0002] The printed circuit board (PCB) in the related art is provided with a component, the component can be a metal oxide semiconductor field effect transistor (MOSFET) or other component with thin thickness, the component can bear assembly stress in the packaging process, the printed circuit board can heat in the use process, the heat can cause the local deformation of the printed circuit board, and the component bears thermal stress, and the above two kinds of stress can all cause the component to break down. SUMMARY

[0003] Therefore, the utility model provides a circuit board assembly and battery to solve the problem that the component on the printed circuit board breaks down under the action of stress.

[0004] In a first aspect, the utility model provides a kind of circuit board assembly, comprising: printed circuit board, is equipped with conductive area;Thermal conductive hard shell is connected with the printed circuit board, and is equipped with installation cavity, and the printed circuit board covers the installation cavity;Component, is installed in the installation cavity, and is connected with the conductive area.

[0005] Beneficial effect: the circuit board assembly of the utility model, by installing component in thermal conductive hard shell, then thermal conductive hard shell is connected with printed circuit board, to realize the connection of component and the conductive area on printed circuit board, on the basis of guaranteeing that the function of circuit board assembly can be realized, stress in the packaging process of circuit board assembly acts on thermal conductive hard shell, can reduce the assembly stress that component bears.In addition, the heat generated in the working process of circuit board assembly can be diffused to air by thermal conductive hard shell, to reduce the heat of the area where component is, avoid local heat concentration to cause the deformation of printed circuit board and component thermal expansion and cold shrink, and then the thermal stress that component bears can be reduced.Even if printed circuit board is deformed because of the heat generated in the working process, thermal stress acts on thermal conductive hard shell, and will not directly act on component, further avoid the thermal stress that component bears, reduce the probability of component stress damage.

[0006] In an alternative embodiment, the inner wall surface of the installation cavity is provided with a first insulating layer.

[0007] Beneficial effects: It can improve the insulation withstand voltage coefficient of the thermally conductive hard shell, prevent electrical conduction between components and the thermally conductive hard shell, reduce the probability of short circuits and other circuit failures in the circuit board assembly, and improve the circuit reliability of the circuit board assembly.

[0008] In one optional embodiment, a flexible heat-conducting element is provided between the inner wall of the mounting cavity and the component.

[0009] Beneficial effects: Increases the heat exchange efficiency between components and the thermally conductive hard shell, further prevents thermal stress caused by heat concentration, and effectively reduces the probability of component damage.

[0010] In one alternative embodiment, the outer surface of the thermally conductive rigid shell is provided with a second insulating layer.

[0011] Beneficial effects: It can improve the insulation withstand voltage coefficient of the thermally conductive rigid shell, so as to avoid electrical connection between the thermally conductive rigid shell and the outside world, reduce the probability of circuit failures such as short circuits in the circuit board assembly, and improve the circuit reliability of the circuit board assembly.

[0012] In one optional embodiment, the printed circuit board includes: a board body having the conductive area; and a solder joint disposed on the board body and soldered to the thermally conductive rigid shell, wherein the solder joint is insulated from the conductive area.

[0013] Beneficial effects: The connection between the printed circuit board and the thermally conductive rigid shell is convenient and has high connection strength, which helps to ensure the relative position between the printed circuit board and the thermally conductive rigid shell.

[0014] In one alternative embodiment, the thermally conductive rigid shell has a notch in a direction perpendicular to the printed circuit board, and the projection of the notch on the printed circuit board is at least partially located on the solder joint.

[0015] Beneficial effects: It allows observation of the welding status of the thermally conductive rigid shell and the welded parts, avoids welding defects, ensures welding yield, and thus ensures the connection stability between the thermally conductive rigid shell and the circuit board.

[0016] In one optional embodiment, the side of the thermally conductive rigid shell that is welded to the weldment is provided with a nickel plating layer; the side of the weldment that is welded to the thermally conductive rigid shell is provided with a solder layer.

[0017] Beneficial effects: It helps improve the reliability of the connection between the thermally conductive rigid shell and the printed circuit board.

[0018] In one optional embodiment, the thermally conductive rigid shell includes: a main body connected to the printed circuit board and having the mounting cavity; and a heat sink connected to the side of the main body and spaced apart from the printed circuit board.

[0019] Beneficial effects: It can increase the heat dissipation area of ​​the thermally conductive hard shell, thereby improving the heat exchange efficiency between the thermally conductive hard shell and the air, thus improving the heat dissipation efficiency of the components, preventing thermal stress caused by heat concentration, and reducing the probability of component damage.

[0020] In one optional embodiment, there are multiple components, which are spaced apart and all located within the mounting cavity; there are multiple conductive areas, which are spaced apart and connected to the multiple components one by one.

[0021] Beneficial effects: Multiple components can be installed using a single thermally conductive rigid shell, eliminating the need for a separate thermally conductive rigid shell for each component. This reduces the number of parts, increases assembly efficiency, and lowers production costs and weight.

[0022] Secondly, this utility model also provides a battery, comprising: a battery cell; and a circuit board assembly as described in the first aspect, wherein the printed circuit board and the battery cell are electrically connected.

[0023] Beneficial effects: The battery of this utility model, through the above-mentioned circuit board assembly, can realize the status monitoring of the battery cell, ensure electrical safety, and the circuit board assembly has a high yield, which can increase the yield of the battery. Attached Figure Description

[0024] To more clearly illustrate the specific embodiments of this utility model 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 this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0025] Figure 1 This is one of the structural schematic diagrams of the circuit board assembly according to an embodiment of the present utility model;

[0026] Figure 2 for Figure 1 A sectional view along line AA.

[0027] Figure 3 for Figure 2 A magnified view of part A in the diagram;

[0028] Figure 4 This is a second schematic diagram of the circuit board assembly according to an embodiment of the present utility model;

[0029] Figure 5 This is an exploded view of the circuit board assembly according to an embodiment of the present utility model;

[0030] Figure 6This is a schematic diagram of the structure of the thermally conductive rigid shell of the circuit board assembly according to an embodiment of the present utility model.

[0031] Figure 7 This is a schematic diagram showing the connection between the circuit board assembly and the flexible circuit board in an embodiment of the present invention.

[0032] Explanation of reference numerals in the attached figures:

[0033] 1. Circuit board assembly;

[0034] 100. Printed circuit board; 101. Conductive area; 110. Board body; 120. Soldered component; 121. Solder layer;

[0035] 200. Thermally conductive rigid shell; 201. Mounting cavity; 202. First insulating layer; 203. Nickel plating layer; 204. Second insulating layer; 206. Notch; 210. Main body; 220. Heat sink;

[0036] 300. Components; 400. Flexible circuit boards. Detailed Implementation

[0037] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0038] In the description of this utility model, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying 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, and therefore should not be construed as a limitation of this utility model.

[0039] In the description of this utility model, "a plurality of" means two or more. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0040] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" 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 utility model according to the specific circumstances.

[0041] In the lithium battery manufacturing process, some lithium batteries pass production line testing, but after assembly into end products (such as mobile phones, tablets, or vehicles), they exhibit a problem where they cannot be turned on even after being shut down. The inventors analyzed this problem and found that the main issues lie in the assembly stress that the components on the printed circuit board may experience during the packaging process, and the deformation of the printed circuit board due to thermal expansion and contraction during use. This deformation can also cause the components to experience thermal stress, and both types of stress can lead to component breakage and failure.

[0042] For example, metal-oxide-semiconductor field-effect transistors (MOSFETs) on printed circuit boards may be subjected to assembly stress during chip-scale packaging (CSP). During the use of the printed circuit board, the area where the MOSFET is located may be subject to thermal stress. Since the common thickness of MOSFETs is about 0.1 mm, and MOSFETs are relatively thin and have a large area, they are prone to breakage failure due to stress.

[0043] The following is combined with Figures 1 to 7 The following describes embodiments of the present invention.

[0044] According to an embodiment of the present invention, a circuit board assembly 1 is provided, which includes a printed circuit board 100, a thermally conductive rigid shell 200, and components 300.

[0045] The printed circuit board 100 has a conductive area 101. A thermally conductive rigid shell 200 is connected to the printed circuit board 100, and the thermally conductive rigid shell 200 has a mounting cavity 201. The printed circuit board 100 covers the mounting cavity 201. Components 300 are mounted in the mounting cavity 201 and are connected to the conductive area 101. Components 300 can be metal-oxide-semiconductor field-effect transistors. The hardness of the thermally conductive rigid shell 200 is greater than the hardness of the component 300.

[0046] For example, component 300 and thermally conductive rigid shell 200 can be connected by adhesive, thermally conductive adhesive, or thermally conductive grease. The hardness of the thermally conductive rigid shell 200 is not less than 400 HRC, for example, it can be 400 HRC, 450 HRC, 500 HRC, 550 HRC, or 600 HRC; the thermal conductivity of the thermally conductive rigid shell 200 is not less than 1300 W / m·K, for example, it can be 1300 W / m·K, 1350 W / m·K, 1400 W / m·K, 1450 W / m·K, or 1500 W / m·K; the thermally conductive rigid shell 200 can be made of metal or composite metal materials, for example, it can be made of aluminum or aluminum alloy. The thermally conductive rigid shell 200 can be processed by stamping.

[0047] Furthermore, the circuit board assembly 1 can be applied to mobile terminals such as mobile phones and tablets, as well as vehicles. It is connected to the battery and serves as a battery protection board. The circuit board assembly 1 can protect the battery from charging and discharging. It utilizes the integrated circuit (IC) on the circuit board assembly 1 to provide charging management for fast charging protocols such as 20W, 40W, 60W, 80W, and 100W.

[0048] By mounting the component 300 onto the thermally conductive rigid shell 200 and then connecting the thermally conductive rigid shell 200 to the printed circuit board 100, the connection between the component 300 and the conductive area 101 on the printed circuit board 100 is achieved. While ensuring that the function of the circuit board assembly 1 can be realized, the stress of the circuit board assembly 1 during the packaging process is applied to the thermally conductive rigid shell 200, which can reduce the assembly stress borne by the component 300.

[0049] In addition, the heat generated by the circuit board assembly 1 during operation can be diffused into the air through the thermally conductive hard shell 200 to reduce the heat in the area where the component 300 is located, avoid local heat concentration that causes thermal expansion and contraction deformation of the printed circuit board 100 and the component 300, and reduce the thermal stress borne by the component 300.

[0050] Even if the printed circuit board 100 deforms due to the heat generated during operation, the thermal stress will act on the thermally conductive rigid shell 200, rather than directly on the component 300, thus further avoiding the thermal stress borne by the component 300.

[0051] In summary, the circuit board assembly 1 of this utility model, by mounting the components 300 onto the printed circuit board 100 through the thermally conductive rigid shell 200, can not only ensure the normal operation of the circuit board assembly 1, but also reduce the assembly stress and thermal stress borne by the components 300, reduce the probability of component 300 damage, improve the yield of the circuit board assembly 1, and extend the service life of the circuit board assembly 1.

[0052] like Figure 6 As shown, in some embodiments, the inner wall surface of the mounting cavity 201 is provided with a first insulating layer 202. For example, the first insulating layer 202 can be formed by plating, or the first insulating layer 202 can be an insulating film directly attached to the thermally conductive rigid shell 200.

[0053] By setting the first insulating layer 202, the insulation withstand voltage coefficient of the thermally conductive hard shell 200 can be improved, for example, the insulation withstand voltage coefficient of the thermally conductive hard shell 200 can reach more than 500V, which can prevent electrical conduction between the component 300 and the thermally conductive hard shell 200, reduce the probability of circuit failures such as short circuits in the circuit board assembly 1, and improve the circuit reliability of the circuit board assembly 1.

[0054] In some embodiments not shown, a flexible thermally conductive element (not shown in the figure) is provided between the inner wall of the mounting cavity 201 and the component 300. This flexible thermally conductive element can be a thermally conductive pad, thermally conductive silicone, or other parts with good thermal conductivity.

[0055] The flexible thermal conductive component can fill the gap between the inner wall of the mounting cavity 201 and the component 300, increase the heat exchange efficiency between the component 300 and the thermally conductive rigid shell 200, further prevent thermal stress caused by heat concentration, and effectively reduce the probability of damage to the component 300.

[0056] like Figure 1 and Figure 4 As shown, in some embodiments, the outer surface of the thermally conductive rigid shell 200 is provided with a second insulating layer 204. The outer surface of the thermally conductive rigid shell 200 refers to the surface of the thermally conductive rigid shell 200 exposed to the outside, that is, the surface of the thermally conductive rigid shell 200 that is not connected to the printed circuit board 100.

[0057] For example, the second insulating layer 204 can be formed by plating, or the second insulating layer 204 can be an insulating film that is directly attached to the thermally conductive rigid shell 200.

[0058] By setting a second insulating layer 204, the insulation withstand voltage coefficient of the thermally conductive hard shell 200 can be improved, for example, the insulation withstand voltage coefficient of the thermally conductive hard shell 200 can reach more than 500V, so as to avoid the thermally conductive hard shell 200 from being electrically connected to the outside world, reduce the probability of circuit failures such as short circuits in the circuit board assembly 1, and improve the circuit reliability of the circuit board assembly 1.

[0059] like Figures 1-5 As shown, in some embodiments, the thermally conductive rigid shell 200 includes a main body 210 and a heat sink 220. The main body 210 is connected to the printed circuit board 100 and has a mounting cavity 201. The heat sink 220 is connected to the side of the main body 210 and is spaced apart from the printed circuit board 100.

[0060] By incorporating heat sink 220, the heat dissipation area of ​​the thermally conductive rigid shell 200 can be increased, thereby improving the heat exchange efficiency between the thermally conductive rigid shell 200 and the air, thus enhancing the heat dissipation efficiency of the component 300, preventing thermal stress caused by heat concentration, and reducing the probability of damage to the component 300. Furthermore, the heat sink 220 is spaced apart from the printed circuit board 100, avoiding interference with the structure of the printed circuit board 100.

[0061] like Figures 1-4 As shown, in some embodiments, the printed circuit board 100 includes a board body 110 and a solder joint 120. The board body 110 is provided with a conductive area 101, the solder joint 120 is disposed on the board body 110, and the solder joint 120 is soldered to the thermally conductive rigid shell 200. The solder joint 120 is insulated from the conductive area 101.

[0062] Among them, the welded part 120 can be metallic copper or copper alloy.

[0063] In this way, the connection between the printed circuit board 100 and the thermally conductive rigid shell 200 is convenient and the connection strength is high, which helps to ensure the relative position between the printed circuit board 100 and the thermally conductive rigid shell 200.

[0064] Furthermore, the thermally conductive rigid shell 200 is provided with a notch 206, and the projection of the notch 206 on the circuit board is at least partially located on the solder joint 120 in a direction perpendicular to the printed circuit board 100.

[0065] The notch 206 allows observation of the welding status between the thermally conductive rigid shell 200 and the weldment 120, preventing welding defects, ensuring welding yield, and thus guaranteeing the connection stability between the thermally conductive rigid shell 200 and the circuit board.

[0066] like Figure 6 As shown, in some embodiments, a nickel-plated layer 203 is provided on the side where the thermally conductive rigid shell 200 is welded to the weldment 120. A solder layer 121 is provided on the side where the weldment 120 is welded to the thermally conductive rigid shell 200. This makes the connection between the thermally conductive rigid shell 200 and the weldment 120 more convenient.

[0067] For example, the solder layer 121 can be printed using surface mount technology (SMT), and the components of the printed circuit board 100 can also be mounted using SMT and then baked in a furnace.

[0068] By setting the nickel plating layer 203, not only can the generation of tin whiskers be suppressed, reducing the probability of short circuits and other circuit failures during use of the circuit board assembly 1, but also the internal stress of the solder layer 121 can be reduced due to the low stress of the nickel plating layer 203. The solder layer 121 is less prone to blistering, peeling and other phenomena. The soldering effect between the nickel plating layer 203 and the printed circuit board 100 is good, which is conducive to improving the connection reliability between the thermally conductive hard shell 200 and the printed circuit board 100.

[0069] like Figure 2 , Figure 3 and Figure 5 As shown, in some embodiments, there are multiple components 300, which are spaced apart and all located within the mounting cavity 201. There are multiple conductive areas 101, which are spaced apart and connected to each of the multiple components 300 in a one-to-one correspondence.

[0070] In this way, multiple components 300 can be installed through a single thermally conductive rigid shell 200, eliminating the need for a separate thermally conductive rigid shell 200 for each component 300. This reduces the number of parts, increases assembly efficiency, and lowers production costs and weight.

[0071] According to an embodiment of this utility model, another aspect provides a battery, which includes a battery cell and the aforementioned circuit board assembly 1, with the printed circuit board 100 electrically connected to the battery cell. The battery can be used in electrical devices such as vehicles, mobile phones, tablets, and laptops, and can be a lithium-ion battery.

[0072] For example, the printed circuit board 100 and the battery cell are connected by two nickel plates. One nickel plate is connected to the positive terminal of the battery cell, and the other nickel plate is connected to the negative terminal of the battery cell. Both nickel plates are connected to the printed circuit board 100 so that the printed circuit board 100, the nickel plates and the battery cell form a conductive circuit.

[0073] In addition, such as Figure 7 As shown, a flexible printed circuit board 400 (FPC) is connected to the printed circuit board 100. The flexible printed circuit board 400 carries a connector that can be connected to electrical components on the electrical equipment. The connector can be a board to board connector (BTB) or an FPC flexible flat cable, which facilitates battery replacement and disassembly on the electrical equipment.

[0074] The battery of this invention, through the aforementioned circuit board assembly 1, can monitor the status of the battery cells, ensuring electrical safety. Furthermore, the circuit board assembly 1 has a high yield rate, which can increase the overall yield of the battery.

[0075] Although embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. A circuit board assembly, characterized by The application relates to a printed circuit board (100) provided with a conductive area (101), a heat-conducting hard shell (200) connected with the printed circuit board (100) and provided with a mounting cavity (201), and a component (300) mounted in the mounting cavity (201) and connected with the conductive area (101). An inner wall surface of the mounting cavity (201) is provided with a first insulating layer (202). An inner wall surface of the mounting cavity (201) and the component (300) are provided with a flexible heat-conducting member. An outer surface of the heat-conducting hard shell (200) is provided with a second insulating layer (204).

2. The circuit board assembly of claim 1, wherein, The printed circuit board (100) comprises a board body (110) provided with the conductive area (101) and a welding member (120) arranged on the board body (110) and welded with the heat-conducting hard shell (200), wherein the welding member (120) is arranged in an insulating mode with the conductive area (101).

3. The circuit board assembly of claim 1, wherein, The heat-conducting hard shell (200) is provided with a notch (206) in a direction perpendicular to the printed circuit board (100), and a projection of the notch (206) on the printed circuit board (100) is at least partially located on the welding member (120).

4. The circuit board assembly of claim 1, wherein, A side of the heat-conducting hard shell (200) welded with the welding member (120) is provided with a nickel plating layer (203).

5. The circuit board assembly of any one of claims 1-4, wherein, A side of the welding member (120) welded with the heat-conducting hard shell (200) is provided with a solder layer (121). The heat-conducting hard shell (200) comprises a main body (210) connected with the printed circuit board (100) and provided with the mounting cavity (201) and a heat-dissipating fin (220) connected with a side surface of the main body (210) and arranged in a spaced mode with the printed circuit board (100). The component (300) is multiple, and the multiple components (300) are arranged in a spaced mode and located in the mounting cavity (201).

6. The circuit board assembly of claim 5, wherein, The conductive area (101) is multiple, and the multiple conductive areas (101) are arranged in a spaced mode and connected with the multiple components (300) in a one-to-one mode.

7. The circuit board assembly of claim 5, wherein, The application relates to an electric circuit board assembly (1) comprising an electric core and a printed circuit board (100) according to any one of claims 1 to 9, wherein the printed circuit board (100) and the electric core are electrically connected. ​ 8. The circuit board assembly of any one of claims 1-4, wherein, ​ ​ ​ 9. The circuit board assembly of any one of claims 1-4, wherein, ​ ​ 10. A battery, characterized by ​ ​ ​

Images