Battery voltage detection circuit and battery protection board

Abstract

The embodiment of the utility model provides a battery voltage detection circuit and a battery protection board, and belongs to the technical field of battery detection. The battery voltage detection circuit is electrically connected with the target battery cell; the battery voltage detection circuit comprises a voltage acquisition module and a sampling protection module. The voltage acquisition module is used for acquiring a voltage value generated when the target battery cell is electrified; the voltage acquisition module comprises a switch unit, and the sampling protection module is used for acquiring a voltage value output by the switch unit and comparing the voltage value with a preset voltage threshold range to obtain a voltage detection result; or, the voltage acquisition module comprises a copper sheet unit, and the sampling protection module is used for acquiring the voltage value output by the copper sheet unit, and comparing the voltage value with a preset voltage threshold range to obtain a voltage detection result. According to the voltage detection circuit, the voltage value of the target cell is directly acquired through the voltage acquisition module, a precise resistor does not need to be arranged on the target cell, and the size of the voltage detection circuit can be reduced.

Description

Technical Field

[0001] The present application relates to the technical field of battery detection, and particularly relates to a battery voltage detection circuit and a battery protection board. Background Art

[0002] At present, during the production and testing process of a battery protection board, it is often necessary to detect the voltage of the circuit on the battery protection board. In the existing battery detection circuit, a precision resistor is usually set. The precision resistor is connected in series with the battery cells, and the voltage of the battery is detected by measuring the voltage of the precision resistor. However, the precision resistor has a large volume, and the precision resistor also needs to be connected in parallel with a filter capacitor, which further increases the volume of the voltage detection circuit and affects the space of the battery protection board, and easily causes the internal circuit of the battery protection board to heat up.

[0003] Therefore, how to provide a voltage detection circuit for a battery, reduce the volume of the voltage detection circuit, and reduce the volume of the battery protection board has become an urgent technical problem to be solved. Utility Model Content

[0004] The main purpose of the embodiments of the present application is to propose a battery voltage detection circuit and a battery protection board, aiming to provide a voltage detection circuit for a battery, save the setting of precision resistors, and reduce the volume of the circuit.

[0005] To achieve the above object, a first aspect of the embodiments of the present application proposes a battery voltage detection circuit.

[0006] In some embodiments, the battery voltage detection circuit is electrically connected to a target battery cell; the battery voltage detection circuit includes: a voltage acquisition module and a sampling protection module.

[0007] The voltage acquisition module is electrically connected to the target battery cell, and the voltage acquisition module is configured to: acquire the voltage value generated by the target battery cell when powered on.

[0008] The voltage acquisition module includes a switch unit; the switch unit is electrically connected to the sampling protection module, and the sampling protection module is configured to: acquire the voltage value output by the switch unit, compare the voltage value with a preset voltage threshold range, and obtain a voltage detection result.

[0009] Or,

[0010] The voltage acquisition module includes a copper foil unit; the copper foil unit is electrically connected to the sampling protection module, and the sampling protection module is configured to: acquire the voltage value output by the copper foil unit, compare the voltage value with a preset voltage threshold range, and obtain a voltage detection result.

[0011] In some embodiments, the sampling protection module includes a battery protection chip, a first sampling resistor, and a second sampling resistor;

[0012] The battery protection chip is electrically connected to the first sampling resistor and the second sampling resistor. The first sampling resistor is electrically connected to the voltage acquisition module, and the second sampling resistor is electrically connected to the voltage acquisition module;

[0013] The battery protection chip is configured to: obtain the voltage value output by the voltage acquisition module, and compare the voltage value with the voltage threshold range to obtain the voltage detection result; wherein, if the voltage value is within the voltage threshold range, the voltage detection result indicates that the voltage is normal; if the voltage value exceeds the voltage threshold range, the voltage detection result indicates that the voltage is abnormal.

[0014] In some embodiments, one end of the first sampling resistor is electrically connected to the switch unit, and the other end of the second sampling resistor is electrically connected to the switch unit.

[0015] In some embodiments, the switch unit includes a first MOS transistor and a second MOS transistor;

[0016] The drain of the first MOS transistor is electrically connected to the drain of the second MOS transistor. The source of the first MOS transistor is electrically connected to the first sampling resistor, the source of the second MOS transistor is electrically connected to the second sampling resistor, and the battery protection chip is electrically connected to the gate of the first MOS transistor and the gate of the second MOS transistor.

[0017] In some embodiments, one end of the first sampling resistor is electrically connected to the copper foil unit, and the other end of the second sampling resistor is electrically connected to the copper foil unit.

[0018] In some embodiments, the battery voltage detection circuit further includes: an overcurrent protection module and an interface module;

[0019] The overcurrent protection module is electrically connected to the target battery cell and the voltage acquisition module, and the interface module is electrically connected to the voltage acquisition module;

[0020] The overcurrent protection module is configured to collect current and switch from the conducting state to the off state when the current is greater than or equal to a preset current threshold; the target battery cell supplies power to an external device connected to the interface module through the interface module; the interface module is configured to perform data transmission with the external device.

[0021] In some embodiments, the switch unit further includes a first capacitor, and the sampling protection module further includes a second capacitor;

[0022] One end of the first capacitor is electrically connected to the source electrode of the first MOS transistor, and the other end of the first capacitor is electrically connected to the source electrode of the second MOS transistor; the second capacitor is electrically connected to the battery protection chip.

[0023] In some embodiments, the battery protection chip includes: an overcurrent protection unit, a control unit, a first driving unit, and a second driving unit;

[0024] The control unit is electrically connected to the overcurrent protection unit, the first driving unit, and the second driving unit; the first driving unit is electrically connected to the first MOS transistor, and the second driving unit is electrically connected to the second MOS transistor;

[0025] When the overcurrent protection unit responds that the voltage value exceeds the voltage threshold range, the control unit determines that the voltage detection result indicates an abnormal voltage, and controls the first MOS transistor to be in an off state through the first driving unit, and controls the second MOS transistor to be in an off state through the second driving unit.

[0026] In some embodiments, the battery protection chip further includes a discharge detection unit and a charge detection unit;

[0027] The control unit is electrically connected to the discharge detection unit and the charge detection unit; the overcurrent protection unit is electrically connected to the first sampling resistor and the second sampling resistor, and the discharge detection unit and the charge detection unit are electrically connected to the second capacitor.

[0028] To achieve the above object, a second aspect of the embodiments of the present application provides a battery protection board, which includes the battery voltage detection circuit and the target battery cell described in the first aspect above.

[0029] The battery voltage detection circuit and the battery protection board provided by the present application provide a voltage detection circuit for a battery; in the voltage detection circuit, the voltage acquisition module includes a switch unit, and the voltage value of the target battery cell is directly obtained by the switch unit; alternatively, the voltage acquisition module includes a copper foil unit, and the voltage value of the target battery cell is directly obtained by the copper foil unit; then the sampling protection module compares the voltage value with a preset voltage threshold range to obtain a voltage detection result; the present application realizes the function of detecting the voltage of the battery cell, and there is no need to set a precision resistor to detect the voltage of the target battery cell, thereby reducing the volume of the voltage detection circuit and the volume of the battery protection board, and saving the space occupied by the battery protection board. Description of the Drawings

[0030] Figure 1 It is a block diagram of the battery voltage detection circuit provided by the embodiments of the present application;

[0031] Figure 2It is the circuit schematic diagram of the battery voltage detection circuit provided by an embodiment of the present application;

[0032] Figure 3 It is the circuit schematic diagram of the battery voltage detection circuit provided by another embodiment of the present application;

[0033] Figure 4 It is the module block diagram of the battery protection chip provided by an embodiment of the present application;

[0034] Reference numerals: 10, target battery cell; 20, voltage acquisition module; 30, sampling protection module; U1, battery protection chip; R1, first sampling resistor; R2, second sampling resistor; M1, first MOS transistor; M2, second MOS transistor; CU1, copper clad unit; F1, overcurrent protection module; J1, interface module; C1, first capacitor; C2, second capacitor; 31, overcurrent protection unit; 32, control unit; 33, first driving unit; 34, second driving unit. Detailed implementation manners

[0035] In order to make the objectives, technical solutions and advantages of the present application clearer, the present application will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application, and are not used to limit the present application.

[0036] It should be noted that although the functional modules are divided in the device schematic diagram and the logical sequence is shown in the flowchart, in some cases, the steps shown or described may be executed in a different order from the module division in the device or the sequence in the flowchart. Terms such as "first" and "second" in the specification, claims and the above-mentioned drawings are used to distinguish similar objects, and do not necessarily need to be used to describe a specific order or sequence.

[0037] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field to which the present application belongs. The terms used herein are only for the purpose of describing the embodiments of the present application, and are not intended to limit the present application.

[0038] First, several nouns involved in the present application are analyzed:

[0039] Battery protection board: It is an integrated circuit board that protects rechargeable batteries (such as lithium batteries). The battery protection board can protect the battery and prevent phenomena such as overcharging, over-discharging, overcurrent, and short circuit of the battery.

[0040] The battery voltage detection circuit and the battery protection board provided by the embodiments of the present application will be specifically described through the following embodiments. First, the battery voltage detection circuit in the embodiments of the present application is described.

[0041] Figure 1 It is an optional module block diagram of the battery voltage detection circuit provided by an embodiment of the present application. The battery voltage detection circuit is electrically connected to the target battery cell 10. The battery voltage detection circuit includes: a voltage acquisition module 20 and a sampling protection module 30;

[0042] The voltage acquisition module 20 is electrically connected to the target battery cell 10, and the voltage acquisition module 20 is used for: acquiring the voltage value generated by the target battery cell 10 when powered on;

[0043] The sampling protection module 30 is electrically connected to the voltage acquisition module 20, and the sampling protection module 30 is used for: obtaining the voltage value output by the voltage acquisition module 20, comparing the voltage value with a preset voltage threshold range, and obtaining a voltage detection result;

[0044] The voltage acquisition module 20 includes a switch unit (not shown in the figure); the switch unit is electrically connected to the sampling protection module 30, and the sampling protection module 30 is used for: obtaining the voltage value output by the switch unit, comparing the voltage value with a preset voltage threshold range, and obtaining a voltage detection result;

[0045] Or,

[0046] The voltage acquisition module 20 includes a copper foil unit CU1 (refer to Figure 3 ), the copper foil unit CU1 is electrically connected to the sampling protection module 30, and the sampling protection module 30 is used for: obtaining the voltage value output by the copper foil unit CU1, comparing the voltage value with a preset voltage threshold range, and obtaining a voltage detection result.

[0047] It should be noted that in the prior art, a precision resistor connected in series with the battery cell is usually set, and the voltage of the battery cell is detected by measuring the voltage of the precision resistor. However, the volume of the precision resistor is relatively large, and the precision resistor also needs to be connected in parallel with a filter capacitor, resulting in a relatively large volume of the voltage detection circuit.

[0048] The beneficial effects of the embodiments of the present application include but are not limited to: in the voltage detection circuit, the voltage acquisition module 20 includes a switch unit, and the switch unit directly obtains the voltage value of the target battery cell 10; or, the voltage acquisition module 20 includes a copper foil unit CU1, and the copper foil unit CU1 directly obtains the voltage value of the target battery cell 10; then the sampling protection module 30 compares the voltage value with a preset voltage threshold range to obtain a voltage detection result; the embodiments of the present application realize the function of detecting the voltage of the battery cell, and there is no need to set a precision resistor to detect the voltage of the target battery cell 10, thereby being able to reduce the volume of the voltage detection circuit and the volume of the battery protection board, and saving the space occupied by the battery protection board.

[0049] Specifically, the target battery cell 10 may be one or more battery cells in a battery, a battery pack, or a Battery Management System (BMS), or may also be a battery cell in a vehicle-mounted battery pack. The embodiments of the present application do not limit this.

[0050] Specifically, the switching unit may include a numerically controlled switch or a touch-controlled switch, such as components like MOS transistors and triodes.

[0051] It should be noted that in the embodiments of the present application, through the switching unit or the copper strip unit CU1 in the voltage acquisition module 20, the voltage of the target battery cell 10 can be directly detected, eliminating the use of precision resistors. Thereby, the volume of the battery voltage detection circuit is significantly reduced, the circuit structure is simplified, the number of components on the circuit board is reduced, which helps to reduce production costs; in addition, reducing the circuit volume helps to improve the compactness of the overall design of the battery protection board, realize the miniaturization of the battery protection board, and improve the portability of the battery protection board; if the circuit volume is too large, it may cause the internal lines of the battery protection board to heat up. Therefore, in the embodiments of the present application, reducing the circuit volume can also reduce the heat generation of the internal lines of the battery protection board, improve the reliability of the battery voltage detection circuit, and further improve the safety of the battery protection board.

[0052] Please refer to Figure 2 , in some embodiments, the sampling protection module 30 includes a battery protection chip U1, a first sampling resistor R1, and a second sampling resistor R2;

[0053] The battery protection chip U1 is electrically connected to the first sampling resistor R1 and the second sampling resistor R2. The first sampling resistor R1 is electrically connected to the voltage acquisition module 20, and the second sampling resistor R2 is electrically connected to the voltage acquisition module 20;

[0054] The battery protection chip U1 is used to: obtain the voltage value output by the voltage acquisition module 20, and compare the voltage value with the voltage threshold range to obtain a voltage detection result; wherein, if the voltage value is within the voltage threshold range, the voltage detection result indicates that the voltage is normal; if the voltage value exceeds the voltage threshold range, the voltage detection result indicates that the voltage is abnormal.

[0055] The advantage of this embodiment is that the voltage value is obtained through the voltage acquisition module 20, and then the voltage value is compared with the voltage threshold range by the battery protection chip U1 to obtain a voltage detection result, so as to judge whether the voltage is normal, which can timely detect the voltage of the target battery cell BAT1. At the same time, the first sampling resistor R1 and the second sampling resistor R2 are set to enable the battery protection chip U1 to operate more stably.

[0056] Specifically, the battery protection chip U1 can be a chip of types such as CPU (Central Processing Unit), MCU (Microcontroller Unit), MPU (Microprocessor Unit), PLC (Programmable Logic Controller), etc. The embodiments of the present application do not limit this.

[0057] Specifically, the voltage threshold range can include a maximum voltage threshold and a minimum voltage threshold, and its unit can be V (volt). For example, the voltage threshold range is from 3.5V to 20V.

[0058] In some embodiments, the first sampling resistor R1 is electrically connected to one end of the switch unit, and the second sampling resistor R2 is electrically connected to the other end of the switch unit.

[0059] The advantage of this embodiment is that under the first connection structure, the first sampling resistor R1 and the second sampling resistor R2 of the sampling protection module 30 are respectively connected to the switch unit in the voltage acquisition module 20, and the voltage of the switch unit is obtained, thereby detecting the voltage of the target battery cell BAT1.

[0060] Please refer to Figure 2 , in some embodiments, the switch unit (not shown in the figure) includes a first MOS transistor M1 and a second MOS transistor M2;

[0061] The drain of the first MOS transistor M1 is electrically connected to the drain of the second MOS transistor M2. The source of the first MOS transistor M1 is electrically connected to the first sampling resistor R1, and the source of the second MOS transistor M2 is electrically connected to the second sampling resistor R2. The battery protection chip U1 is electrically connected to the gates of the first MOS transistor M1 and the second MOS transistor M2.

[0062] The advantage of this embodiment is that by obtaining the voltages of the first MOS transistor M1 and the second MOS transistor M2, the voltage of the target battery cell BAT1 is detected, and the voltage value of the target battery cell BAT1 is directly obtained, without setting a precision resistor to detect the voltage of the target battery cell BAT1, thereby being able to reduce the volume of the voltage detection circuit and reduce the volume of the battery protection board.

[0063] It should be noted that in the battery voltage detection circuit, the voltage acquisition module 20 can simultaneously include a switch module and a copper foil unit CU1 (refer to Figure 2), where the first MOS transistor M1 and the second MOS transistor M2 of the switch module are used to collect the voltage of the target battery cell 10 and output a voltage value, and the copper foil unit CU1 is equivalent to a wire; in another embodiment, the voltage acquisition module 20 may also include only the first MOS transistor M1 and the second MOS transistor M2, without including the copper foil unit CU1.

[0064] Please refer to Figure 3 , in some embodiments, the first sampling resistor R1 is electrically connected to one end of the copper foil unit CU1, and the second sampling resistor R2 is electrically connected to the other end of the copper foil unit CU1.

[0065] The advantage of this embodiment is that, under the second connection structure, the first sampling resistor R1 and the second sampling resistor R2 of the sampling protection module 30 are respectively connected to the copper foil unit CU1 in the voltage acquisition module 20, and the voltage of the switch unit is obtained, so as to detect the voltage of the target battery cell BAT1.

[0066] It should be noted that, in the battery voltage detection circuit, the voltage acquisition module 20 may include both the switch module and the copper foil unit CU1 (refer to Figure 3 ), where the copper foil unit CU1 is used to collect the voltage of the target battery cell 10 and output a voltage value, and the first MOS transistor M1 and the second MOS transistor M2 of the switch module are used to control the conduction or disconnection between the battery voltage detection circuit and the target battery cell 10; in another embodiment, the voltage acquisition module 20 may also include only the copper foil unit CU1, without including the first MOS transistor M1 and the second MOS transistor M2.

[0067] Please refer to Figure 2 or Figure 3 , in some embodiments, the battery voltage detection circuit further includes: an overcurrent protection module F1 and an interface module J1;

[0068] The overcurrent protection module F1 is electrically connected to the target battery cell BAT1 and the voltage acquisition module 20, and the interface module J1 is electrically connected to the voltage acquisition module 20;

[0069] The overcurrent protection module F1 is used to collect current, and switch from the conducting state to the disconnect state when the current is greater than or equal to a preset current threshold; the target battery cell BAT1 supplies power to an external device connected to the interface module J1 through the interface module J1; the interface module J1 is used for data transmission with the external device.

[0070] The advantage of this embodiment is that the overcurrent protection module F1 prevents the current in the circuit from being too large, and the interface module J1 supplies power to the external device and conducts data transmission.

[0071] Specifically, the overcurrent protection module F1 can be a fuse. It should be noted that the fuse can be a low-melting-point metal wire or metal sheet, and the fuse has a preset current rating. When the current passing through the fuse exceeds the current rating, the fuse will quickly blow, thereby cutting off the circuit and preventing the circuit from being damaged due to excessive current.

[0072] Please refer to Figure 2 or Figure 3 , in some embodiments, the switch unit further includes a first capacitor C1, and the sampling protection module 30 further includes a second capacitor C2; one end of the first capacitor C1 is electrically connected to the source electrode of the first MOS transistor M1, and the other end of the first capacitor C1 is electrically connected to the source electrode of the second MOS transistor M2; the second capacitor C2 is electrically connected to the battery protection chip U1.

[0073] Please refer to Figure 4 , in some embodiments, the battery protection chip U1 includes: an overcurrent protection unit 31, a control unit 32, a first drive unit 33, and a second drive unit 34;

[0074] The control unit 32 is electrically connected to the overcurrent protection unit 31, the first drive unit 33, and the second drive unit 34; the first drive unit 33 is electrically connected to the first MOS transistor M1, and the second drive unit 34 is electrically connected to the second MOS transistor M2;

[0075] When the overcurrent protection unit 31 responds to the voltage value exceeding the voltage threshold range, the control unit 32 determines that the voltage detection result indicates an abnormal voltage, and controls the first MOS transistor M1 to be in an off state through the first drive unit 33, and controls the second MOS transistor M2 to be in an off state through the second drive unit 34.

[0076] In some embodiments, the battery protection chip U1 further includes a discharge detection unit (not labeled in the figure) and a charge detection unit (not labeled in the figure);

[0077] The control unit 32 is electrically connected to the discharge detection unit and the charge detection unit; the overcurrent protection unit 31 is electrically connected to a first sampling resistor R1 and a second sampling resistor R2, and the discharge detection unit and the charge detection unit are electrically connected to the second capacitor C2.

[0078] It should be noted that the discharge detection unit and the charge detection unit are respectively electrically connected to both ends of the second capacitor C2, jointly obtain the voltage of the second capacitor C2, and send the voltage to the control unit 32. The control unit 32 determines the state of the second capacitor C2 as a discharge state or a charge state according to the voltage data, and compares the voltage with a preset voltage threshold to obtain a voltage detection result.

[0079] Specifically, if the voltage is greater than or equal to the voltage threshold, the voltage detection result is normal voltage; if the voltage is less than the voltage threshold, the voltage detection result is abnormal voltage.

[0080] The advantage of this embodiment is that the discharge detection unit and the charge detection unit are electrically connected to the second capacitor C2, so as to detect the charge and discharge state of the second capacitor C2 and avoid excessive voltage during the charge and discharge of the battery cell.

[0081] The embodiment of the present application further provides a battery protection board, which includes the above-mentioned battery voltage detection circuit and the target battery cell BAT1.

[0082] The specific implementation manner of this battery protection board is basically the same as that of the above-mentioned specific embodiment of the battery voltage detection circuit, and will not be elaborated here.

[0083] The embodiments described in the embodiments of the present application are for more clearly explaining the technical solutions of the embodiments of the present application, and do not constitute a limitation on the technical solutions provided by the embodiments of the present application. Those skilled in the art can know that with the evolution of technology and the emergence of new application scenarios, the technical solutions provided by the embodiments of the present application are also applicable to similar technical problems.

[0084] Those skilled in the art can understand that the technical solutions shown in the figures do not constitute a limitation on the embodiments of the present application, and may include more or fewer steps than shown in the figures, or combine some steps, or different steps.

[0085] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separated, that is, they may be located in one place, or may be distributed to multiple network units. Some or all of the modules can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0086] Those of ordinary skill in the art can understand that the functional modules / units in the circuits, systems, products or devices disclosed above can be implemented as firmware, hardware and their appropriate combinations.

[0087] The terms "first", "second", "third", "fourth", etc. (if any) in the specification of the present application and the above-mentioned drawings are used to distinguish similar objects, and do not have to be used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged under appropriate circumstances, so that the embodiments of the present application described here can be implemented in an order other than those illustrated or described here. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a system, product or device including a series of steps or units does not have to be limited to those steps or units clearly listed, but may include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0088] It should be understood that in this application, "at least one (item)" means one or more, and "a plurality" means two or more. "And / or" is used to describe the association relationship of associated objects, indicating that there can be three relationships. For example, "A and / or B" can mean: only A exists, only B exists, and both A and B exist at the same time. Among them, A and B can be singular or plural. The character " / " generally indicates that the associated objects before and after are in an "or" relationship. "At least one (item) of the following" or its similar expression refers to any combination of these items, including any combination of single item (item) or plural items (items). For example, at least one (item) of a, b, or c can mean: a, b, c, "a and b", "a and c", "b and c", or "a and b and c", where a, b, c can be single or multiple.

[0089] In several embodiments provided in this application, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the device embodiments described above are only illustrative. For example, the above-mentioned unit division is only a logical function division. In actual implementation, there can be other division methods. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. The displayed or discussed coupling or direct coupling or communication connection to each other can be through some interfaces. The indirect coupling or communication connection of devices or units can be in electrical, mechanical or other forms.

[0090] The units described above as separate components may or may not be physically separated. The components shown as units may or may not be physical units, that is, they can be located in one place, or they can be distributed to multiple network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0091] In addition, in each embodiment of this application, each functional unit can be integrated in a processing unit, or each unit can exist physically alone, or two or more units can be integrated in one unit. The above-mentioned integrated unit can be implemented in the form of hardware or in the form of a software functional unit.

[0092] The preferred embodiments of the embodiments of this application have been described above with reference to the drawings, but this does not limit the scope of rights of the embodiments of this application. Any modifications, equivalent replacements, and improvements made by those skilled in the art without departing from the scope and essence of the embodiments of this application shall be within the scope of rights of the embodiments of this application.

Claims

1. A battery voltage detection circuit, characterized in that, The battery voltage detection circuit is electrically connected to the target battery cell; the battery voltage detection circuit includes: a voltage acquisition module and a sampling protection module; The voltage acquisition module is electrically connected to the target battery cell, and the voltage acquisition module is configured to: acquire the voltage value generated by the target battery cell when powered on; The voltage acquisition module includes a switch unit; the switch unit is electrically connected to the sampling protection module, and the sampling protection module is configured to: obtain the voltage value output by the switch unit, and compare the voltage value with a preset voltage threshold range to obtain a voltage detection result; Or, The voltage acquisition module includes a copper foil unit; the copper foil unit is electrically connected to the sampling protection module, and the sampling protection module is configured to: obtain the voltage value output by the copper foil unit, and compare the voltage value with a preset voltage threshold range to obtain a voltage detection result.

2. The battery voltage detection circuit according to claim 1, wherein The sampling protection module includes a battery protection chip, a first sampling resistor, and a second sampling resistor; The battery protection chip is electrically connected to the first sampling resistor and the second sampling resistor, the first sampling resistor is electrically connected to the voltage acquisition module, and the second sampling resistor is electrically connected to the voltage acquisition module; The battery protection chip is configured to: obtain the voltage value output by the voltage acquisition module, and compare the voltage value with the voltage threshold range to obtain the voltage detection result; wherein, if the voltage value is within the voltage threshold range, the voltage detection result indicates normal voltage; If the voltage value exceeds the voltage threshold range, the voltage detection result indicates abnormal voltage.

3. The battery voltage detection circuit according to claim 2, characterized in that, The first sampling resistor is electrically connected to one end of the switch unit, and the second sampling resistor is electrically connected to the other end of the switch unit.

4. The battery voltage detection circuit according to claim 3, wherein, The switch unit includes a first MOS transistor and a second MOS transistor; The drain of the first MOS transistor is electrically connected to the drain of the second MOS transistor, the source of the first MOS transistor is electrically connected to the first sampling resistor, the source of the second MOS transistor is electrically connected to the second sampling resistor, and the battery protection chip is electrically connected to the gates of the first MOS transistor and the second MOS transistor.

5. The battery voltage detection circuit according to claim 2, wherein The first sampling resistor is electrically connected to one end of the copper foil unit, and the second sampling resistor is electrically connected to the other end of the copper foil unit.

6. The battery voltage detection circuit according to any one of claims 1 to 5, characterized in that The battery voltage detection circuit further includes: an overcurrent protection module and an interface module; The overcurrent protection module is electrically connected to the target battery cell and the voltage acquisition module, and the interface module is electrically connected to the voltage acquisition module; The overcurrent protection module is configured to collect current and switch from a conducting state to a non-conducting state when the current is greater than or equal to a preset current threshold; the target battery cell supplies power to an external device connected to the interface module through the interface module; the interface module is configured to perform data transmission with the external device.

7. The battery voltage detection circuit according to claim 4, wherein The switch unit further includes a first capacitor, and the sampling protection module further includes a second capacitor; One end of the first capacitor is electrically connected to the source of the first MOS transistor, and the other end of the first capacitor is electrically connected to the source of the second MOS transistor; The second capacitor is electrically connected to the battery protection chip.

8. The battery voltage detection circuit according to claim 7, wherein The battery protection chip includes: an overcurrent protection unit, a control unit, a first driving unit, and a second driving unit; The control unit is electrically connected to the overcurrent protection unit, the first driving unit, and the second driving unit; the first driving unit is electrically connected to the first MOS transistor, and the second driving unit is electrically connected to the second MOS transistor; In response to the voltage value exceeding the voltage threshold range, the overcurrent protection unit causes the control unit to determine that the voltage detection result indicates an abnormal voltage, and controls the first MOS transistor to be in an off state through the first driving unit, and controls the second MOS transistor to be in an off state through the second driving unit.

9. The battery voltage detection circuit according to claim 8, wherein, The battery protection chip further includes a discharge detection unit and a charge detection unit; The control unit is electrically connected to the discharge detection unit and the charge detection unit; the overcurrent protection unit is electrically connected to the first sampling resistor and the second sampling resistor, and the discharge detection unit and the charge detection unit are electrically connected to the second capacitor.

10. A battery protection board, characterized in that, The battery protection board includes the battery voltage detection circuit according to any one of claims 1 to 9 and the target battery cell.

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