A battery management circuit and energy storage system

Abstract

The present application discloses a battery management circuit and energy storage system, which includes a first switch module, a second switch module, an energy storage module and a control module. The energy storage module is connected to the battery, and the energy storage module is used to charge when connected to the battery to output a first voltage. The first switch module is connected to the energy storage module, and the first switch module is used to turn on when the first voltage is less than the first voltage threshold to output a second voltage. The control module is respectively connected to the first switch module, the second switch module and the battery, and the control module is used to start timing when the second voltage is received. If the timing duration is greater than or equal to the first duration, the second switch module is controlled to disconnect to disconnect the connection between the control module and the battery. In the above manner, the power consumption of the battery can be reduced to near zero when the battery is not in use, thereby extending the service life of the battery.

Description

Technical Field

[0001] The present application relates to the field of battery technology, and in particular to a battery management circuit and energy storage system. Background Art

[0002] Since the invention of lithium batteries, more and more products have been powered by lithium batteries, making the equipment used in human work and life more and more convenient to use. However, there are strict requirements for the working environment of lithium batteries. Overcharging and over-discharging are not allowed to occur, otherwise the battery may be easily damaged and cause fire and explosion.

[0003] Specifically, when lithium batteries are not in use, they typically require a low-power design to prevent damage from over-discharge. Currently, when lithium batteries are not in use, a low-power microcontroller unit (MCU) is typically used to control the lithium battery to enter sleep mode to reduce power consumption.

[0004] However, this approach cannot reduce the power consumption of the lithium battery to near zero when the lithium battery is not in use. In other words, the lithium battery still has a certain power consumption, which means there is still a risk of damage due to over-discharge. Summary of the Invention

[0005] The embodiments of the present application aim to provide a battery management circuit and energy storage system that can reduce the power consumption of the battery to near zero when the battery is not in use, thereby extending the service life of the battery.

[0006] To achieve the above objectives, in a first aspect, the present application provides a battery management circuit, comprising:

[0007] A first switch module, a second switch module, an energy storage module and a control module;

[0008] The energy storage module is connected to the battery, and the energy storage module is used to charge when connected to the battery to output a first voltage;

[0009] The first switch module is connected to the energy storage module, and the first switch module is configured to be turned on when the first voltage is less than a first voltage threshold to output a second voltage;

[0010] The control module is connected to the first switch module, the second switch module and the battery respectively. The control module is configured to start timing when receiving the second voltage. If the timing duration is greater than or equal to the first duration, the control module controls the second switch module to disconnect, thereby disconnecting the connection between the control module and the battery.

[0011] In an optional manner, the control module includes a first switch unit, a first control unit and a second control unit;

[0012] The first switch unit is connected to the battery, the first control unit, the first switch module, the second switch module and the energy storage module respectively, and the first switch unit is configured to be disconnected when the second switch module is disconnected, so as to disconnect the first control unit from the battery;

[0013] The first control unit is connected to the second control unit, and the first control unit is used to provide input power to the second control unit;

[0014] The second control unit is connected to the first switch module and the second switch module. The second control unit is used to start timing when receiving the second voltage, and control the second switch module to disconnect if the timing duration is greater than or equal to the first duration.

[0015] In an optional manner, the first switch unit includes a first switch tube and a first resistor;

[0016] The first end of the first switching tube is respectively connected to the first switching module, the second switching module and the energy storage module, the second end of the first switching tube is connected to the positive electrode of the battery and the second switching module, and the third end of the first switching tube is connected to the power input end of the first control unit through the first resistor.

[0017] In an optional manner, the first switch module includes a second switch tube, a second resistor and a third resistor;

[0018] A first end of the second switch tube is connected to the energy storage module, a second end of the second switch tube is connected to the control module, the energy storage module and the second switch module, a third end of the second switch tube is connected to the first end of the second resistor, a second end of the second resistor is connected to the control module and the first end of the third resistor, and a second end of the third resistor is grounded.

[0019] In an optional manner, the second switch module includes a third switch tube, a fourth resistor, a fifth resistor, a sixth resistor and a seventh resistor;

[0020] The first end of the third switching tube is connected to the first end of the fourth resistor and the first end of the fifth resistor, the second end of the fourth resistor is grounded, the second end of the fifth resistor is connected to the control module, the second end of the third switching tube is grounded, the third end of the third switching tube is connected to the first end of the sixth resistor, the second end of the sixth resistor is connected to the first end of the seventh resistor, the control module, the first switching module and the energy storage module, and the second end of the seventh resistor is connected to the battery and the control module.

[0021] In an optional manner, the energy storage module includes a voltage dividing unit, a second switch unit and an energy storage unit;

[0022] The voltage dividing unit is respectively connected to the battery, the control module, the first switch module, the second switch module and the second switch unit, and the second switch unit is connected to the energy storage unit;

[0023] The energy storage unit is configured to be charged when the second switch unit is turned on, so as to output the first voltage;

[0024] The voltage dividing unit is configured to output a fourth voltage when the first voltage is less than a first voltage threshold, wherein the fourth voltage is configured to control the first switch module to be turned on.

[0025] In an optional manner, the voltage dividing unit includes an eighth resistor and a ninth resistor;

[0026] The eighth resistor and the ninth resistor are connected in series to form a first branch, the first end of the first branch is connected to the control module, the first switch module and the second switch module, the second end of the first branch is connected to the second switch unit, and the connection point between the eighth resistor and the ninth resistor is connected to the first switch module.

[0027] In an optional manner, the second switch unit includes a button;

[0028] The first end of the button is connected to the voltage dividing unit, and the second end of the button is connected to the energy storage unit.

[0029] In an optional manner, the energy storage unit includes a first capacitor and a tenth resistor;

[0030] The first capacitor is connected in parallel with the tenth resistor, a first end of the first capacitor is connected to the second switch unit, and a second end of the capacitor is grounded.

[0031] In a second aspect, the present application provides an energy storage system, comprising at least one battery and the battery management circuit as described above, wherein the battery is connected to the battery management circuit.

[0032] The beneficial effects of the embodiments of the present application are as follows: the battery management circuit provided by the present application includes a first switch module, a second switch module, an energy storage module and a control module. The energy storage module is connected to the battery, the first switch module is connected to the energy storage module, and the control module is connected to the first switch module, the second switch module and the battery respectively. If the battery has been used, the energy storage module can be charged when connected to the battery to output a first voltage. When the first voltage is less than the first voltage threshold, the first switch module is turned on to output a second voltage. Then, the control module starts timing when receiving the second voltage, and controls the second switch module to disconnect when the timing duration is greater than or equal to the first duration, so as to disconnect the connection between the control module and the battery when the battery is not in use. At this time, since the connection between the battery and the control module has been disconnected, the power consumption of the battery can be reduced to near zero, thereby reducing the risk of damage to the battery due to over-discharge, which is conducive to extending the service life of the battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] One or more embodiments are exemplarily illustrated by pictures in the corresponding drawings. These exemplifications do not constitute limitations on the embodiments. Elements with the same reference numerals in the drawings are represented as similar elements. Unless otherwise stated, the figures in the drawings do not constitute proportional limitations.

[0034] Figure 1 A schematic diagram of the structure of a battery management circuit provided in an embodiment of the present application;

[0035] Figure 2 A schematic structural diagram of a battery management circuit provided in another embodiment of the present application;

[0036] Figure 3 A schematic diagram of the circuit structure of the battery management circuit provided in an embodiment of the present application. DETAILED DESCRIPTION

[0037] To make the purpose, technical solutions, and advantages of the embodiments of this application more clear, the technical solutions in the embodiments of this application will be clearly and completely described below in conjunction with the drawings in the embodiments of this application. Obviously, the described embodiments are part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0038] With the emergence of lithium batteries in recent years, more and more products have adopted them for power supply, making the equipment used in our daily lives and work more and more convenient. However, lithium batteries have strict operating environment requirements and must not be overcharged or over-discharged, otherwise they can easily damage the battery and cause fire and explosion.

[0039] Therefore, lithium batteries are typically designed to consume less power when not in use to prevent damage from overdischarge. For example, in one application scenario, a user activates a lithium battery only to check the battery charge status on an electronic device such as a display. After the user checks the battery, the battery is no longer in use. If it remains activated, it will continue to discharge, posing a risk of damage from overdischarge.

[0040] During the process of implementing this application, the inventors discovered that, in current related technologies, a low-power MCU is typically selected to reduce battery power consumption when the battery is not in use. However, this approach, on the one hand, is generally expensive, leading to increased costs; on the other hand, it is also impossible for this MCU to achieve near-zero power consumption, meaning the battery still consumes power, which in turn still carries the risk of over-discharging the battery.

[0041] Based on this, an embodiment of the present application provides a battery management circuit. This battery management circuit disconnects the battery from the control module in the battery management circuit after the user activates the battery, that is, after the battery has been used, if the battery is not used again within a preset period of time, so that the battery stops outputting power. Thus, when the battery is not in use, the power consumption of the battery is reduced to near zero, which can prevent the battery from being over-discharged and help extend the battery life. At the same time, the present application can use a conventional MCU, which is lower in cost than the low-power MCU selected in the related art.

[0042] Please refer to Figure 1 , Figure 1 This is a schematic diagram of the structure of the battery management circuit provided in the embodiment of the present application. Figure 1 As shown, the battery management circuit 100 includes a first switch module 10 , a second switch module 20 , an energy storage module 30 and a control module 40 . The battery management circuit 100 is used to connect to a battery 200 .

[0043] The energy storage module 30 is connected to the battery 200, the first switch module 10 is connected to the energy storage module 30, and the control module 40 is connected to the first switch module 10, the second switch module 20, and the battery 200. Specifically, the first end of the first switch module 10 is connected to the first end of the second switch module 20, the first end of the energy storage module 30, and the first end of the control module 40. The second end of the first switch module 10 is connected to the second end of the control module 40. The third end of the first switch module 10 is connected to the second end of the energy storage module 30, the second end of the second switch module 20 is connected to the third end of the control module 40, and the third end of the second switch module 20 is connected to the fourth end of the control module 40 and the battery 200.

[0044] In this embodiment, the energy storage module 30 is configured to charge when connected to the battery 200, thereby outputting a first voltage. The first switch module 10 is configured to conduct when the first voltage is less than a first voltage threshold, thereby outputting a second voltage. The control module 40 is configured to output a first control signal based on the second voltage. Specifically, upon receiving the second voltage, the control module 40 begins timing. If the timing duration is greater than or equal to the first duration, the control module 40 outputs a first control signal to control the second switch module 20 to disconnect, thereby disconnecting the control module 40 from the battery 200.

[0045] It is understood that the first duration can be set according to actual application conditions and is not limited in this embodiment of the present application. For example, in one embodiment, the user activates the battery only to check the power level of the battery 200. In this case, the first duration can be set to a shorter duration, such as 1 minute, to stop the battery 200 from outputting power in a timely manner, which is conducive to saving power consumption of the battery 200.

[0046] Specifically, when the battery 200 needs to be used, it is necessary to establish a connection between the battery 200 and the energy storage module 30, and to establish a connection between the battery 200 and the control module 40, so as to connect the battery 200 to the energy storage module 30 and the control module 40, that is, both the energy storage module 30 and the control module 40 are powered.

[0047] Subsequently, the energy storage module 30 is charged, generating a first voltage within the energy storage module 30 and inputting the first voltage into the first switch module 10. When the voltage is less than a first voltage threshold, the first switch module 10 turns on, and when the voltage is greater than the first voltage threshold, the first switch module 10 turns off. After the first switch module 10 turns on, it outputs a second voltage and inputs the second voltage into the second terminal of the control module 40. After receiving the second voltage, the control module 40 disconnects the energy storage module 30 from the battery 200. Simultaneously, upon receiving the second voltage, the control module 40 begins timing. If the timing duration is greater than or equal to the first duration, the third terminal of the control module 40 outputs a first control signal to the second terminal of the second switch module 20, causing the second switch module 20 to turn off. After the second switch module 20 turns off, the control module 40 disconnects the second switch module 20 from the battery 200.

[0048] Thus, when the battery 200 is not in use, the connection between the battery 200 and the energy storage module 30 and the control module 40 is disconnected, reducing the power consumption of the battery 200 to near zero. This prevents damage to the battery 200 due to over-discharge, improves power safety, and extends the service life of the battery 200. Furthermore, the battery 200 can provide relatively stable power, which helps improve the operational stability of the battery management circuit 100.

[0049] It should be noted that the battery in the embodiments of the present application can be a lithium-ion battery, a lithium metal battery, a lead-acid battery, a nickel-cathode battery, a nickel-metal hydride battery, a lithium-sulfur battery, a lithium-air battery, or a sodium-ion battery, etc., and is not limited here. In terms of scale, the battery in the embodiments of the present application can be a single cell, or a battery module composed of multiple single cells connected in series and / or in parallel, or a battery pack composed of multiple battery modules connected in series and / or in parallel, or a power supply device composed of multiple battery packs connected in parallel, and is not limited here.

[0050] In one embodiment, if Figure 2 As shown, the control module 40 includes a first switch unit 41, a first control unit 42, and a second control unit 43. The first switch unit 41 is connected to the battery 200, the first control unit 42, the first switch module 10, the second switch module 20, and the energy storage module 30, respectively. The first control unit 42 is connected to the second control unit 43, and the second control unit 43 is connected to the first switch module 10 and the second switch module 20. Specifically, the first end of the first switch unit 41 is connected to the battery 200 and the third end of the second switch module 20, respectively. The second end of the first switch unit 41 is connected to the first end of the first switch module 10, the first end of the second switch module 20, and the first end of the energy storage module 30, respectively. The third end of the first switch unit 41 is connected to the first end of the first control unit 42, the second end of the first control unit 42 is connected to the first end of the second control unit 43, the second end of the second control unit 43 is connected to the third end of the first switch module 10, and the third end of the second control unit 43 is connected to the second end of the second switch module 20.

[0051] Among them, the second end of the first switch unit 41 is the first end of the control module 40, the second end of the second control unit 43 is the second end of the control module 40, the third end of the second control unit 43 is the third end of the control module 40, and the first end of the first switch unit 41 is the fourth end of the control module 40.

[0052] Specifically, the first switch unit 41 is configured to disconnect when the second switch module 20 is disconnected, thereby disconnecting the first control unit 42 from the battery 200. The first control unit 42 is configured to provide input power to the second control unit 43. The second control unit 43 is configured to start timing upon receiving the second voltage and, if the timing duration is greater than or equal to the first duration, control the second switch module 20 to disconnect.

[0053] In one embodiment, please combine Figure 2 Reference Figure 3 The first switch unit 41 includes a first switch tube Q1 and a first resistor R1. The first switch tube Q1 is a PMOS tube as an example.

[0054] A first end of the first switch tube Q1 is connected to the first switch module 10, the second switch module 20, and the energy storage module 30, respectively. A second end of the first switch tube Q1 is connected to the positive electrode of the battery 200 and the second switch module 20. A third end of the first switch tube Q1 is connected to the power input terminal VCC of the first control unit 42 via the first resistor R1.

[0055] In this embodiment, when the first switch Q1 is turned on, the positive electrode of the battery 200 is connected to the power input terminal VCC of the first control unit 42, and the first control unit 42 is powered. Conversely, when the first switch Q1 is turned off, the connection between the positive electrode of the battery 200 and the first control unit 42 is severed, and the first control unit 42 loses power. The first resistor R1 is used to limit current, preventing damage to the first control unit 42 due to excessive current, thereby protecting the first control unit 42.

[0056] In one embodiment, the first control unit 42 provides input power to the power input terminal VDD of the second control unit 43 through its power output terminal REGOUT, so that the second control unit 43 obtains a power supply voltage.

[0057] In one embodiment, the input terminal IN1 of the second control unit 43 is used to input the second voltage, and the output terminal OUT1 thereof outputs a first control signal to control the second switch module 20 to be disconnected, or outputs a second control signal to control the second switch module 20 to be connected.

[0058] In summary, in practical applications, when the battery 200 is needed, the first switch Q1 should be turned on to power the first control unit 42 and the second control unit 43. Furthermore, as can be seen from the above embodiment, at this time, the second control unit 43 can receive a second voltage at its input terminal IN1, and the second control unit 43 begins timing upon receiving the second voltage. If the timing duration is greater than or equal to the first duration, a first control signal is output from the output terminal OUT1 to control the second switch module 20 to disconnect, thereby turning off the first switch Q1. Consequently, both the first control unit 42 and the second control unit 43 lose power, and the power consumption of the battery 200 is reduced to nearly zero.

[0059] It is understood that when the time duration measured by the second control unit 43 is less than the first time duration, the second control unit 43 can output a second control signal through its output terminal OUT1 to control the second switch module 20 to be turned on. In this case, the second switch module 20 can output a fifth voltage, which can keep the first switch Q1 turned on, thereby keeping the first control unit 42 and the second control unit 43 powered, which is conducive to maintaining stable operation of the battery management circuit 100.

[0060] In one embodiment, the first switch module 10 includes a second switch transistor Q2, a second resistor R2, and a third resistor R3. The first end of the second switch transistor Q2 is connected to the second end of the energy storage module 30, the second end of the second switch transistor Q2 is connected to the first end of the control module 40, the first end of the energy storage module 30, and the first end of the second switch module 20. The third end of the second switch transistor Q2 is connected to the first end of the second resistor R2, the second end of the second resistor R2 is connected to the second end of the control module 40 and the first end of the third resistor R3, and the second end of the third resistor R3 is grounded GND. In this embodiment, the second switch transistor Q2 is a PMOS transistor.

[0061] Specifically, when the second switch Q2 is turned on, the second resistor R2 and the third resistor R3 act as a voltage divider to obtain a second voltage at the connection point between the second resistor R2 and the third resistor R3. When the second switch Q2 is turned off, the voltage at the connection point between the second resistor R2 and the third resistor R3 is 0. Therefore, when the battery 200 is needed, the second switch Q2 can be turned on to input the second voltage to the input terminal IN1 of the second control unit 43, so that the second control unit 43 is informed that the battery 200 has been used.

[0062] In one embodiment, the second switch module 20 includes a third switch transistor Q3, a fourth resistor R4, a fifth resistor R5, a sixth resistor R6, and a seventh resistor R7. A first end of the third switch transistor Q3 is connected to a first end of the fourth resistor R4 and a first end of the fifth resistor R, a second end of the fourth resistor R4 is grounded GND, a second end of the fifth resistor R5 is connected to a third end of the control module 40, a second end of the third switch transistor Q3 is grounded GND, a third end of the third switch transistor Q3 is connected to a first end of the sixth resistor R6, a second end of the sixth resistor R6 is connected to a first end of the seventh resistor R7, a first end of the control module 40, a first end of the first switch module 10, and a first end of the energy storage module 30, and a second end of the seventh resistor R7 is connected to the battery 200 and a fourth end of the control module 40. In this embodiment, the third switch transistor Q3 is an NMOS transistor.

[0063] Specifically, the fifth resistor R5 acts as a current limiter to prevent damage to the first terminal of the third switch Q3 due to excessive input current. Simultaneously, the second resistor R5 and the fourth resistor R4 act as a voltage divider to divide the voltage outputted from the output terminal OUT1 of the second control unit 43. When the divided voltage across the fourth resistor R4 is greater than the turn-on voltage of the third switch Q3, the third switch Q3 is turned on; otherwise, the third switch Q3 is turned off. Therefore, the divided voltage across the fourth resistor R4 of the voltage of the first control signal outputted from the output terminal OUT1 of the second control unit 43 should be less than the turn-on voltage of the third switch Q3, while the divided voltage across the fourth resistor R4 of the voltage of the second control signal should be greater than the turn-on voltage of the third switch Q3.

[0064] The seventh resistor R7 also functions as a current limiter to prevent damage to the first terminal of the first switch Q1 due to excessive input current. Simultaneously, the sixth resistor R6 and the seventh resistor R7 function as a voltage divider to divide the voltage output by the battery 200. When the divided voltage across the seventh resistor R7 is greater than the turn-on voltage of the first switch Q1, the first switch Q1 is turned on; otherwise, the first switch Q1 is turned off. It will be understood that in this embodiment, the divided voltage across the seventh resistor R7 represents the fifth voltage output by the second switch module 20 in the aforementioned embodiment.

[0065] In one embodiment, the energy storage module 30 includes a voltage divider unit 31, a second switch unit 32, and an energy storage unit 33. The voltage divider unit 31 is respectively connected to the battery 200, the control module 30, the first switch module 10, the second switch module 20, and the second switch unit 32, and the second switch unit 32 is connected to the energy storage unit 33. Specifically, a first end of the voltage divider unit 31 is respectively connected to a first end of the first switch module 10, a first end of the second switch module 20, and a first end of the control module 40; a second end of the voltage divider unit 31 is connected to a second end of the first switch module 10; a third end of the voltage divider unit 31 is connected to a first end of the second switch unit 32; and a second end of the second switch unit 32 is connected to a first end of the energy storage unit 33.

[0066] The first end of the voltage dividing unit 31 is the first end of the energy storage module 30 , and the second end of the voltage dividing unit 31 is the second end of the energy storage module 30 .

[0067] Specifically, the energy storage unit 33 is used to charge when the second switch unit 32 is turned on to output a first voltage. The voltage divider unit 31 is used to output a fourth voltage when the first voltage is less than the first voltage threshold, wherein the fourth voltage is used to control the first switch module 10 to turn on.

[0068] In one embodiment, the voltage divider unit 31 includes an eighth resistor R8 and a ninth resistor R9. The eighth resistor R8 and the ninth resistor R9 are connected in series to form a first branch. A first end of the first branch is connected to a first end of the control module 40, a first end of the first switch module 10, and a first end of the second switch module 20. A second end of the first branch is connected to the second switch unit 32. The connection point between the eighth resistor R8 and the ninth resistor R9 is connected to a third end of the first switch module 10.

[0069] Specifically, the eighth resistor R8 functions as a current limiter to prevent damage to the first terminal of the second switch Q2 due to excessive input current. Simultaneously, the eighth resistor R8 and the ninth resistor R9 function as a voltage divider to divide the voltage output by the battery 200. When the divided voltage across the eighth resistor R8 is greater than the turn-on voltage of the second switch Q2, the second switch Q2 is turned on; otherwise, the second switch Q2 is turned off. It will be understood that in this embodiment, the divided voltage across the eighth resistor R8 is the fourth voltage output by the voltage divider unit 31 in the aforementioned embodiment.

[0070] In one embodiment, the second switch unit 32 includes a button K1 , wherein a first end of the button K1 is connected to the voltage dividing unit 31 , and a second end of the button K1 is connected to the energy storage unit 33 .

[0071] Specifically, when the button K1 is pressed, the energy storage unit 33 is connected to the battery 200 and the energy storage unit 33 is charged. When the button K1 is released, the connection between the energy storage unit 33 and the battery 200 is disconnected and the energy storage unit 33 is discharged.

[0072] In one embodiment, the energy storage unit 33 includes a first capacitor C1 and a tenth resistor R10 , wherein the first capacitor C1 and the tenth resistor R10 are connected in parallel, a first end of the first capacitor C1 is connected to the second switch unit 32 , and a second end of the first capacitor C1 is grounded GND.

[0073] Specifically, when the button K1 is pressed, the first capacitor C1 is charged by the voltage divided by the output voltage of the battery 200 across the tenth resistor R10. When the button K1 is disconnected, the first capacitor C1 is discharged through the tenth resistor R10.

[0074] In one embodiment, if Figure 3 As shown, the battery management circuit 100 further includes a clamping module 50, wherein the clamping module includes a first Zener diode DW1 and a second Zener diode DW2. The anode of the first Zener diode DW1 is connected to the first end of the first switch transistor Q1, the second end of the second switch transistor Q2, and the cathode of the second Zener diode DW2. The cathode of the first Zener diode DW1 is connected to the second end of the first switch transistor Q1 and the positive electrode of the battery 200. The anode of the second Zener diode DW2 is connected to the first end of the second switch transistor Q2.

[0075] In this embodiment, the first zener diode DW1 is used to clamp the voltage between the first and second terminals of the first switch tube Q1 (i.e., the fifth voltage) to prevent the voltage between the first and second terminals of the first switch tube Q1 from being excessively high and damaging the first switch tube Q1, thereby improving the stability of the first switch tube Q1. The second zener diode DW2 is used to clamp the voltage between the first and second terminals of the second switch tube Q2 (i.e., the fourth voltage) to prevent the voltage between the first and second terminals of the second switch tube Q2 from being excessively high and damaging the second switch tube Q2, thereby improving the stability of the second switch tube Q2.

[0076] In one embodiment, the battery management circuit 100 further includes a filter module 60. The filter module 60 includes an eleventh resistor R11 and a second capacitor C2. A first end of the eleventh resistor R11 is connected to the positive electrode of the battery 200, a second end of the eleventh resistor R11 is connected to the first end of the second capacitor C2 and the first voltage detection terminal VC1 of the first control unit 42, and a second end of the second capacitor C2 is connected to the negative electrode of the battery 200 and the second voltage detection terminal VC2 of the first control unit 42.

[0077] Specifically, the eleventh resistor R11 and the second capacitor C2 are used to filter out high-frequency interference signals in the voltage output by the battery 200, so that the first control unit 42 can detect a relatively stable voltage. The first voltage detection terminal VC1 and the second voltage detection terminal VC2 are used to detect the voltage across the battery 200 to obtain the charge level of the battery 200.

[0078] It is understood that in this embodiment, the power level of one battery 200 is obtained as an example. In other embodiments, if the power levels of N batteries 200 need to be detected separately, a corresponding filter module 60 can be provided for each battery 200, where N is a positive integer.

[0079] In one embodiment, the battery management circuit 100 further includes a third switch module 70 and a first diode D1. The third switch module 70 includes a fourth switch transistor Q4 and a fifth switch transistor Q5. A first terminal of the fourth switch transistor Q4 is connected to the first control terminal DSG of the first control unit 42, a second terminal of the fourth switch transistor Q4 is connected to the negative electrode of the battery 200, a third terminal of the fourth switch transistor Q4 is connected to the third terminal of the fifth switch transistor Q5 and to a port S4, a first terminal of the fifth switch transistor Q5 is connected to the second control terminal CHG of the first control unit 42, a second terminal of the fifth switch transistor Q5 is connected to a port S3, an anode of the first diode D1 is connected to a port S2, and a cathode of the first diode D1 is connected to a first terminal of a fifth resistor R5 and an output terminal OUT1 of the second control unit 43. The positive electrode of the battery 200 is also connected to the port S1. In this embodiment, the fourth switch transistor Q4 is an NMOS transistor, and the fifth switch transistor Q5 is a PMOS transistor.

[0080] In this embodiment, interface S1 can be used to connect to the positive terminal of an external device, including a charging device and a power-consuming device. When interface S1 is connected to the charging device, interface S3 is used to connect to the negative terminal of the charging device. When interface S1 is connected to the power-consuming device, interface S4 is used to connect to the negative terminal of the power-consuming device. Interface S2 is used to input a high-level signal through the external device when connected to the external device, thereby turning on the third switch Q3 and the first switch Q1, thereby energizing the first control unit 42 and the second control unit 43.

[0081] Then, if a charging device is connected to charge battery 200, the first control terminal DSG outputs a control signal to turn on fourth switch Q4, and the second output terminal CHG outputs a control signal to turn on fifth switch Q5, forming a circuit between battery 200 and the charging device, and charging battery 200. If a consumer is connected to power battery 200, the first control terminal DSG outputs a control signal to turn on fourth switch Q4, forming a circuit between the consumer and the battery, and battery 200 is used to provide power to the consumer.

[0082] It should be noted that, in the embodiments of the present application, each switch tube may be a switching device such as a triode, a MOS tube, or an IGBT switch tube, and each switch tube may be the same or different.

[0083] Take the first switch Q1 as an example. If the first switch Q1 is a transistor, the base of the transistor is the first terminal of the first switch Q1, the emitter of the transistor is the second terminal of the first switch Q1, and the collector of the transistor is the third terminal of the first switch Q1. If the first switch Q1 is a MOS transistor, the gate of the MOS transistor is the first terminal of the first switch Q1, the source of the MOS transistor is the second terminal of the first switch Q1, and the drain of the MOS transistor is the third terminal of the first switch Q1. If the first switch Q1 is an IGBT, the gate of the IGBT is the first terminal of the first switch Q1, the emitter of the IGBT is the second terminal of the first switch Q1, and the collector of the IGBT is the third terminal of the first switch Q1.

[0084] In order to better understand this application, Figure 3 The working principle of the circuit structure shown is introduced.

[0085] When the battery management circuit 100 is not connected to an external device, the battery 200 is activated to check the battery level. First, the button K1 is pressed, forming a circuit with the battery 200, the seventh resistor R7, the eighth resistor R8, the ninth resistor R9, the button K1, and the first capacitor C1. The first capacitor C1 is charged, and a first voltage is generated across the first capacitor C1, which gradually increases.

[0086] When the first voltage is less than the first voltage threshold, the difference between the voltage of the battery 200 and the first voltage is large, and a large voltage division can be obtained on the seventh resistor R7 and the eighth resistor R8, that is, the fourth voltage is obtained at both ends of the seventh resistor R7, and the fifth voltage is obtained at both ends of the eighth resistor R8.

[0087] On the one hand, the fourth voltage turns on the first switch Q1, energizing the first control unit 42 and the second control unit 43. The first control unit 42 obtains the battery 200 charge level via the first and second voltage detection terminals VC1 and VC2, and transmits the information to the third control unit 43 via the connection lines SDA and SCL. The third control unit 43 can control a corresponding display device to display the battery 200 charge level for the user to view.

[0088] On the other hand, the fifth voltage turns on the second switch Q2. The battery 200, the seventh resistor R7, the second switch Q2, the second resistor R2, and the third resistor R3 form a loop to output a second voltage value to the input terminal IN1 of the second control unit 43. The third control unit 43 begins timing and outputs a second control signal (currently a high-level signal) from the output terminal OUT1 to turn on the third switch Q3. At this time, the battery 200, the seventh resistor R7, the sixth resistor R6, and the third switch Q3 form a loop to maintain the fourth voltage across the seventh resistor R7, thereby keeping the first switch Q1 conductive.

[0089] When the first voltage increases to a value greater than or equal to the first voltage threshold, the difference between the battery 200 voltage and the first voltage is small. Consequently, the fifth voltage across the eighth resistor R8 decreases to approximately 0V, while the fourth voltage across the seventh resistor R7 remains constant due to the circuitry connected by the battery 200, the seventh resistor R7, the sixth resistor R6, and the third switch Q3. Consequently, the second switch Q2 is turned off, while the first switch Q1 remains on, maintaining power to both the first control unit 42 and the second control unit 43, allowing the battery 200 charge level to continue to be displayed.

[0090] Then, when the timer counted by the second control unit 43 is greater than or equal to the first duration, the output terminal OUT1 of the second control unit 43 outputs a first control signal (a low-level signal in this case) to turn off the third switch Q3. At this point, the fourth voltage across the seventh resistor R7 also drops to zero, turning off the first switch Q1. The connection between the first control unit 42 and the battery 200 is severed, and both the first control unit 42 and the second control unit 43 lose power.

[0091] Thus, through the above method, the process of querying the battery 200 power level is achieved. Moreover, after the user checks the battery 200, the connection between the battery 200 and the first control unit 41 can be controlled to be disconnected after a certain period of time, thereby reducing the power consumption of the battery 200 to nearly zero. This can prevent the battery 200 from being damaged by over-discharge, which is conducive to extending the service life of the battery 200.

[0092] Meanwhile, in this embodiment, when an abnormal situation occurs in which the button K1 is continuously pressed, the power consumption of the battery 200 can be kept close to zero by selecting appropriate types of electronic components in the battery management circuit 100 .

[0093] For example, in one embodiment, due to a malfunction of the button K1, the button K1 cannot be disconnected after being pressed, that is, the button K1 remains pressed. In this case, the first capacitor C1 remains in a charging state until the voltage across it is equal to the voltage across the tenth resistor R10. Furthermore, the difference V0 between the voltage of the battery 200 and the voltage across the tenth resistor R10 is divided across the seventh resistor R7 to form the fourth voltage. Furthermore, the difference V0 between the voltage of the battery 200 and the voltage across the tenth resistor R10 is divided across the eighth resistor R8 to form the fifth voltage.

[0094] Therefore, to keep the power consumption of the battery 200 close to zero, the first switch Q1 and the third switch Q3 must be disconnected when the battery 200 is not in use. Specifically, the fourth voltage must be less than the conduction voltage of the first switch Q1, and the fifth voltage must be less than the conduction voltage of the second switch Q2. Consequently, the difference V0 must be kept small to minimize the fourth and fifth voltages. Therefore, while maintaining the output voltage of the battery 200, the voltage across the tenth resistor R10 can be increased to minimize the difference V0. In other words, by selecting a resistor with a larger resistance as the tenth resistor R10, the first switch Q1 and the second switch Q2 can be kept disconnected even in the event of an abnormal situation where the key K1 is continuously pressed.

[0095] Therefore, when the battery 200 is not in use, the power consumption of the battery 200 can be kept close to 0, so as to avoid damage to the battery 200 due to over-discharge, which is beneficial to extending the service life of the battery 200.

[0096] An embodiment of the present application further provides an energy storage system, which includes at least one battery and the battery management circuit of any embodiment of the present application, wherein the battery is connected to the battery management circuit.

[0097] In one embodiment, the energy storage system is a battery pack.

[0098] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Based on the concept of the present application, the technical features in the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other variations in different aspects of the present application as described above. For the sake of simplicity, they are not provided in detail. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A battery management circuit, characterized in that: include: A first switch module, a second switch module, an energy storage module and a control module; The first end of the first switch module is connected to the first end of the second switch module, the first end of the energy storage module, and the first end of the control module; the second end of the first switch module is connected to the second end of the control module; the third end of the first switch module is connected to the second end of the energy storage module; the second end of the second switch module is connected to the third end of the control module; and the third end of the second switch module is connected to the fourth end of the control module and the battery; The energy storage module is configured to be charged when connected to the battery to output a first voltage; The first switch module is configured to be turned on when the first voltage is less than a first voltage threshold to output a second voltage, and the first switch module is further configured to be turned off when the first voltage is greater than or equal to the first voltage threshold; The control module is configured to start timing upon receiving the second voltage and control the second switch module to be turned on, and if the timing duration is greater than or equal to the first duration, control the second switch module to be turned off, so as to disconnect the control module from the battery; The control module includes a first switch unit, a first control unit and a second control unit; The first switch unit is connected to the battery, the first control unit, the first switch module, the second switch module and the energy storage module respectively, and the first switch unit is configured to be disconnected when the second switch module is disconnected, so as to disconnect the first control unit from the battery; The first control unit is connected to the second control unit, and the first control unit is used to provide input power to the second control unit; The second control unit is connected to the first switch module and the second switch module, and is configured to start timing when receiving the second voltage, and control the second switch module to disconnect if the timing duration is greater than or equal to the first duration; The energy storage module includes a voltage dividing unit, a second switch unit and an energy storage unit; The voltage dividing unit is respectively connected to the battery, the control module, the first switch module, the second switch module and the second switch unit, and the second switch unit is connected to the energy storage unit; The energy storage unit is configured to be charged when the second switch unit is turned on, so as to output the first voltage; The voltage dividing unit is configured to output a fourth voltage when the first voltage is less than a first voltage threshold, wherein the fourth voltage is configured to control the first switch module to be turned on.

2. The battery management circuit according to claim 1, characterized in that: The first switch unit includes a first switch tube and a first resistor; The first end of the first switching tube is respectively connected to the first switching module, the second switching module and the energy storage module, the second end of the first switching tube is connected to the positive electrode of the battery and the second switching module, and the third end of the first switching tube is connected to the power input end of the first control unit through the first resistor.

3. The battery management circuit according to claim 1, characterized in that: The first switch module includes a second switch tube, a second resistor and a third resistor; A first end of the second switch tube is connected to the energy storage module, a second end of the second switch tube is connected to the control module, the energy storage module and the second switch module, a third end of the second switch tube is connected to the first end of the second resistor, a second end of the second resistor is connected to the control module and the first end of the third resistor, and a second end of the third resistor is grounded.

4. The battery management circuit according to claim 1, characterized in that: The second switch module includes a third switch tube, a fourth resistor, a fifth resistor, a sixth resistor and a seventh resistor; The first end of the third switching tube is connected to the first end of the fourth resistor and the first end of the fifth resistor, the second end of the fourth resistor is grounded, the second end of the fifth resistor is connected to the control module, the second end of the third switching tube is grounded, the third end of the third switching tube is connected to the first end of the sixth resistor, the second end of the sixth resistor is connected to the first end of the seventh resistor, the control module, the first switching module and the energy storage module, and the second end of the seventh resistor is connected to the battery and the control module.

5. The battery management circuit according to claim 1, characterized in that: The voltage dividing unit includes an eighth resistor and a ninth resistor; The eighth resistor and the ninth resistor are connected in series to form a first branch, the first end of the first branch is connected to the control module, the first switch module and the second switch module, the second end of the first branch is connected to the second switch unit, and the connection point between the eighth resistor and the ninth resistor is connected to the first switch module.

6. The battery management circuit according to claim 5, characterized in that: The second switch unit includes a button; The first end of the button is connected to the voltage dividing unit, and the second end of the button is connected to the energy storage unit.

7. The battery management circuit according to claim 5, characterized in that: The energy storage unit includes a first capacitor and a tenth resistor; The first capacitor is connected in parallel with the tenth resistor, a first end of the first capacitor is connected to the second switch unit, and a second end of the capacitor is grounded.

8. An energy storage system, characterized in that: The device comprises at least one battery and a battery management circuit according to any one of claims 1 to 7, wherein the battery is connected to the battery management circuit.

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