Battery protection board and battery module

Abstract

The utility model discloses a battery protection board and a battery module, and relates to the technical field of energy storage equipment. The battery protection board comprises a PCB, a control IC and an MOS switch, the control IC is arranged on the surface of the PCB, the MOS switch is embedded in the PCB, and the MOS switch is electrically connected with the control IC and the PCB. According to the scheme, the problem that an existing battery protection plate is large in size can be solved.

Description

Technical Field

[0001] The present application belongs to the technical field of energy storage equipment, and specifically relates to a battery protection board and a battery module. Background Art

[0002] Battery protection board usually refers to lithium battery protection board. This is mainly determined by the material of the lithium battery itself, which cannot be overcharged, over-discharged, over-current and short-circuited. Therefore, a special battery protection board is set for protection. It monitors the voltage of the battery body and the current of the charging and discharging circuit in an environment of -40℃ to +85℃, and controls the on and off of the current circuit in time.

[0003] The battery protection board mainly includes PCB (printed circuit board), control IC (Integrated Circuit), MOS (MOSFET, Metal-Oxide-Semiconductor Field-Effect Transistor) switch, precision resistor and auxiliary device NTC (Negative Temperature Coefficient) thermistor, ID memory, etc. Among them, the control IC controls the MOS switch to turn on when everything is normal, so that the battery body is connected to the external circuit, and when the battery body voltage or loop current exceeds the specified value, it immediately (tens of milliseconds) controls the MOS switch to turn off to protect the safety of the battery body. Usually, the control IC and MOS switch are both set on the surface of the PCB board, which takes up a certain space, which leads to the larger size of the battery protection board. Utility Model Content

[0004] The purpose of the embodiments of the present application is to provide a battery protection board and a battery module, which can solve the problem of the large size of the current battery protection board.

[0005] In order to solve the above technical problems, this application is implemented as follows:

[0006] In a first aspect, an embodiment of the present application provides a battery protection board, comprising a PCB board, a control IC and a MOS switch, wherein the control IC is arranged on the surface of the PCB board, the MOS switch is embedded in the PCB board, and the MOS switch is electrically connected to the control IC and the PCB board, respectively.

[0007] Optionally, the battery protection board further includes a heat insulating component, which is embedded in the PCB board and located between the control IC and the MOS switch.

[0008] Optionally, in a direction perpendicular to the PCB board, the orthographic projection of the control IC is located within the orthographic projection of the thermal insulation component.

[0009] Optionally, in a direction perpendicular to the PCB board, the orthographic projection of the thermal insulation element covers the orthographic projection of the MOS switch.

[0010] Optionally, the PCB board includes an inner layer, a dielectric layer and a surface circuit layer stacked in sequence, the inner layer is provided with a buried hole, the MOS switch is arranged in the buried hole, the MOS switch is electrically connected to the inner circuit layer of the inner layer, the thermal insulation is embedded in the dielectric layer, and the control IC is arranged in the surface circuit layer.

[0011] Optionally, the thermal insulation member is a thermal insulation board, and the thickness of the thermal insulation member is equal to the thickness of the dielectric layer.

[0012] Optionally, the thermal insulation element and the dielectric layer are an integrated structure.

[0013] Optionally, the MOS switch has a first solder pad, the control IC includes a connected main body and a second solder pad, the second solder pad is embedded in the surface circuit layer, the main body is located above the surface circuit layer, the thermal insulation member is provided with a connecting hole, and the first solder pad is electrically connected to the second solder pad through the connecting hole, so that the control IC is electrically connected to the MOS switch.

[0014] Optionally, the thermal insulation element is a vacuum panel.

[0015] In a second aspect, an embodiment of the present application further provides a battery module, comprising a battery body and the above-mentioned battery protection board, wherein the battery protection board is electrically connected to the battery body.

[0016] In the embodiment of the present application, the MOS switch is embedded in the PCB board to avoid occupying the space on the surface of the PCB board. At this time, other devices arranged on the surface of the PCB board can be arranged in a centralized manner, thereby reducing the size of the PCB board and further reducing the size of the entire battery protection board. Therefore, the embodiment of the present application can solve the problem of the current large size of the battery protection board. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 A schematic diagram of the structure of a battery protection board disclosed in an embodiment of the present application;

[0018] Figure 2 A schematic diagram of the partial structure of the battery protection board disclosed in the embodiment of the present application.

[0019] Description of reference numerals:

[0020] 110 - PCB board, 111 - inner layer, 112 - dielectric layer, 113 - surface circuit layer, 120 - control IC, 130 - MOS switch, 140 - thermal insulation. DETAILED DESCRIPTION

[0021] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0022] The terms "first", "second", etc. in the specification and claims of the present application are used to distinguish similar objects, and are not used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable under appropriate circumstances, so that the embodiments of the present application can be implemented in an order other than those illustrated or described here, and the objects distinguished by "first", "second", etc. are generally of one type, and the number of objects is not limited. For example, the first object can be one or more. In addition, "and / or" in the specification and claims represents at least one of the connected objects, and the character " / " generally indicates that the objects associated with each other are in an "or" relationship.

[0023] The battery protection board and battery module provided in the embodiments of the present application are described in detail below through specific embodiments and their application scenarios in conjunction with the accompanying drawings.

[0024] like Figure 1 to Figure 2 As shown, the embodiment of the present application provides a battery protection board, that is, a lithium battery protection board. Optionally, the battery protection board can be applied to lithium iron phosphate battery modules, nickel-acid lithium battery modules, manganese-acid lithium battery modules, cobalt-acid lithium battery modules and other lithium-ion battery modules to play the role of overcharge protection, discharge protection, overcurrent protection and short circuit protection. The battery protection board includes a PCB board 110, a control IC 120 and a MOS switch 130. The control IC 120 is arranged on the surface of the PCB board 110, and the MOS switch 130 is embedded in the PCB board 110. The MOS switch 130 is electrically connected to the control IC 120 and the PCB board 110 respectively. The control IC 120 can control the MOS switch 130 to be turned on under normal circumstances, so that the battery body of the battery module is turned on with the external circuit. When the battery body voltage or loop current exceeds the specified value, it immediately (tens of milliseconds) controls the MOS switch 130 to be turned off to protect the safety of the battery body.

[0025] In the embodiment of the present application, the MOS switch 130 is embedded in the PCB board 110 to avoid occupying the space on the surface of the PCB board 110. At this time, other devices arranged on the surface of the PCB board 110 can be arranged in a centralized manner, thereby reducing the size of the PCB board 110, and then reducing the size of the entire battery protection board. Therefore, the embodiment of the present application can solve the problem of the large size of the current battery protection board. In addition, the embodiment of the present application embeds the MOS switch 130 in the PCB board 110, which can reduce the heat generated by the MOS switch 130 when it is working, and the impact on other devices arranged on the surface of the PCB board 110; at the same time, it can avoid the MOS switch 130 from being damaged by mechanical stress; and after the size of the battery protection board is reduced, it is beneficial to improve the mass energy density of the battery module.

[0026] Since the MOS switch 130 generates a large amount of heat when working, optionally, in a direction perpendicular to the PCB board 110, the control IC 120 and the MOS switch 130 can be staggered to avoid the heat generated by the MOS switch 130 when working to be transferred to the control IC 120, thereby protecting the control IC 120; or, in other embodiments, the battery protection board further includes a heat insulating member 140, which is embedded in the PCB board 110 and located between the control IC 120 and the MOS switch 130, that is, in a direction perpendicular to the PCB board, the control IC 120 and the MOS switch 130 are arranged relative to each other, at this time, the heat generated by the MOS switch 130 when working can be blocked by the heat insulating member 140, thereby avoiding the heat from being transferred to the control IC 120, thereby protecting the control IC 120; and, the distance between the control IC 120 and the MOS switch 130 is small, which is conducive to shortening the signal transmission path between the control IC 120 and the MOS switch 130, thereby reducing the influence of other devices in the signal transmission process.

[0027] In an optional embodiment, in the direction perpendicular to the PCB board 110, the orthographic projection of the control IC 120 is located within the orthographic projection of the thermal insulation member 140, that is, the size of the thermal insulation member 140 is larger than the size of the control IC 120, thereby improving the thermal insulation efficiency of the thermal insulation member 140. Of course, in the direction perpendicular to the PCB board 110, the contour line of the orthographic projection of the control IC 120 and the contour line of the orthographic projection of the thermal insulation member 140 may coincide, that is, the size of the thermal insulation member 140 is equal to the size of the control IC 120.

[0028] Optionally, in the direction perpendicular to the PCB board 110, the orthographic projection of the heat insulating member 140 may be located within the orthographic projection of the MOS switch 130, and in this case, the heat emitted from the edge of the MOS switch 130 may be transferred to the area where the control IC 120 is located. Therefore, in a further optional embodiment, in the direction perpendicular to the PCB board 110, the orthographic projection of the heat insulating member 140 covers the orthographic projection of the MOS switch 130. In other words, the size of the heat insulating member 140 is larger than the size of the MOS switch 130 and the size of the control IC 120 at the same time, thereby further improving the heat insulation effect of the heat insulating member 140.

[0029] In another optional embodiment, the PCB board 110 includes an inner layer 111, a dielectric layer 112, and a surface circuit layer 113 stacked in sequence, the inner layer 111 is provided with a buried hole, and the MOS switch 130 is arranged in the buried hole, which is conducive to saving the surface space of the PCB board 110, thereby making full use of the space in the thickness direction of the PCB board 110 to improve the space utilization rate of other circuit layers. The MOS switch 130 is electrically connected to the inner circuit layer of the inner layer 111, the heat insulation member 140 is embedded in the dielectric layer 112, and the control IC 120 is arranged in the surface circuit layer 113. Optionally, the surface circuit layer 113 can be provided with a blind hole, which is electrically connected to the buried hole of the inner layer 111, so that the MOS switch 130 is electrically connected to the control IC 120.

[0030] Optionally, the heat insulating member 140 is a heat insulating board, and the thickness of the heat insulating member 140 is equal to the thickness of the dielectric layer 112, that is, the side of the heat insulating member 140 facing the surface circuit layer 113 is flush with the side of the dielectric layer 112 facing the surface circuit layer 113, and the side of the heat insulating member 140 facing the inner layer 111 is flush with the side of the dielectric layer 112 facing the inner layer 111, thereby facilitating the arrangement of the surface circuit layer 113 and the inner layer 111. Of course, the thickness of the heat insulating member 140 may also be greater than or less than the thickness of the dielectric layer 112.

[0031] Optionally, the thermal insulation member 140 and the dielectric layer 112 may be a split structure; or, in other embodiments, the thermal insulation member 140 and the dielectric layer 112 are an integrated structure, so that the PCB board 110 can be manufactured by a pressing technology.

[0032] Optionally, the MOS switch 130 and the inner wall of the buried hole and the control IC 120 and the inner wall of the blind hole can be connected by spot welding; or, in another optional embodiment, the MOS switch 130 has a first pad, the control IC 120 includes a main body and a second pad connected to each other, the second pad is embedded in the surface circuit layer 113, the main body is located above the surface circuit layer 113, the heat insulating member 140 is provided with a connection hole, and the first pad is electrically connected to the second pad through the connection hole, so that the control IC 120 is electrically connected to the MOS switch 130. Specifically, the first pad is connected to the copper clad layer on the inner wall of the buried hole, and the second pad is connected to the copper clad layer on the inner wall of the blind hole, thereby increasing the connection area between the control IC 120 and the blind hole and the connection area between the MOS switch 130 and the buried hole, thereby improving the electrical connection stability between the control IC 120 and the MOS switch 130.

[0033] Optionally, the thermal insulation member 140 is a vacuum plate, which has the characteristics of low density and low thermal conductivity, which is conducive to improving the thermal insulation effect of the thermal insulation member 140. Of course, the thermal insulation member 140 can also be a thermal insulation structure such as aerogel felt, and the embodiment of the present application does not specifically limit this.

[0034] In an optional embodiment, the battery protection board also includes a battery protection IC, a current sensing resistor and a capacitor. The battery protection IC, the current sensing resistor and the capacitor can all be arranged on the surface circuit layer 113 of the PCB board 110, wherein the protection IC is used to effectively monitor the charging and discharging status of the battery body, and shut down the charging and discharging circuits under certain conditions to prevent damage to the battery body; the current sensing resistor, also known as the current detection resistor, is connected in series with the device to be detected to sample the current flowing through the device; the capacitor is used to cut off the discharge circuit when the control IC 120 detects that the voltage is lower than a preset value (such as 2.3V) when the battery body is in a discharge state, so that the battery body cannot discharge the load, thereby playing a role in over-discharge protection.

[0035] Optionally, based on the battery protection board disclosed in the embodiment of the present application, the manufacturing method of the battery protection board can be: reserve space for setting the MOS switch 130 in the inner layer 111 of the PCB board 110, and electrically connect the buried hole of the inner layer 111 with the blind hole of the surface circuit layer 113, and the first pad of the control IC 120 is embedded directly above the MOS switch 130, that is, the surface circuit layer 113; embed the MOS switch 130 in the inner layer 111 of the PCB board 110, and the insulation material and the dielectric layer 112 form an integrated structure, and then the inner layer 111, the dielectric layer 112, the surface circuit layer 113 and other layers are pressed together to form the PCB board 110; devices such as protection IC, current sensing resistor, capacitor and so on are arranged on the surface circuit layer 113 of the PCB board 110 to form a complete battery protection board.

[0036] Based on the battery protection board disclosed in the embodiments of the present application, the embodiments of the present application further provide a battery module, which includes a battery body and the battery protection board described in any of the above embodiments, and the battery protection board is electrically connected to the battery body.

[0037] Optionally, the battery module also includes a battery management system and a casing. The battery management system is used to monitor and manage the charging and discharging process of the battery body to ensure the safety and stability of the battery body, and can monitor parameters such as the voltage, temperature and current of the battery body, evaluate and balance the state of the battery body to avoid overcharging, over-discharging, overheating and the like, and provide a communication interface for data exchange with an external system; the battery body is arranged in a housing cavity surrounded by the casing and the battery protection plate, and the casing is used to provide protection and heat dissipation functions.

[0038] The embodiments of the present application are described above in conjunction with the accompanying drawings, but the present application is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the guidance of the present application, ordinary technicians in this field can also make many forms without departing from the purpose of the present application and the scope of protection of the claims, all of which are within the protection of the present application.

Claims

1. A battery protection board, characterized in that: The invention comprises a PCB board (110), a control IC (120) and a MOS switch (130), wherein the control IC (120) is arranged on the surface of the PCB board (110), the MOS switch (130) is embedded in the PCB board (110), and the MOS switch (130) is electrically connected to the control IC (120) and the PCB board (110) respectively.

2. The battery protection board according to claim 1, characterized in that: The battery protection board also includes a heat insulating member (140), wherein the heat insulating member (140) is embedded in the PCB board (110), and the heat insulating member (140) is located between the control IC (120) and the MOS switch (130).

3. The battery protection board according to claim 2, characterized in that: In a direction perpendicular to the PCB board (110), the orthographic projection of the control IC (120) is located within the orthographic projection of the thermal insulation member (140).

4. The battery protection board according to claim 3, characterized in that: In a direction perpendicular to the PCB board (110), the orthographic projection of the heat insulating member (140) covers the orthographic projection of the MOS switch (130).

5. The battery protection board according to claim 2, characterized in that: The PCB board (110) comprises an inner layer (111), a dielectric layer (112) and a surface circuit layer (113) stacked in sequence, the inner layer (111) being provided with a buried hole, the MOS switch (130) being arranged in the buried hole, the MOS switch (130) being electrically connected to the inner circuit layer of the inner layer (111), the heat insulating member (140) being embedded in the dielectric layer (112), and the control IC (120) being arranged in the surface circuit layer (113).

6. The battery protection board according to claim 5, characterized in that: The thermal insulation member (140) is a thermal insulation board, and the thickness of the thermal insulation member (140) is equal to the thickness of the dielectric layer (112).

7. The battery protection board according to claim 6, characterized in that: The thermal insulation component (140) and the dielectric layer (112) are an integrated structure.

8. The battery protection board according to claim 5, characterized in that: The MOS switch (130) has a first pad, the control IC (120) comprises a main body and a second pad connected to each other, the second pad is embedded in the surface circuit layer (113), the main body is located above the surface circuit layer (113), the heat insulating member (140) is provided with a connection hole, the first pad is electrically connected to the second pad through the connection hole, so that the control IC (120) is electrically connected to the MOS switch (130).

9. The battery protection board according to claim 2, characterized in that: The thermal insulation member (140) is a vacuum panel.

10. A battery module, characterized in that: The invention comprises a battery body and a battery protection plate according to any one of claims 1 to 9, wherein the battery protection plate is electrically connected to the battery body.

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