CN216056393U

CN216056393U - Charging control circuit

Info

Publication number: CN216056393U
Application number: CN202122089381.3U
Authority: CN
Inventors: 滕德卿
Original assignee: Svolt Energy Technology Co Ltd
Current assignee: Svolt Energy Technology Co Ltd
Priority date: 2021-08-31
Filing date: 2021-08-31
Publication date: 2022-03-15
Anticipated expiration: 2031-08-31

Abstract

The application provides a charging control circuit, which comprises a charging wake-up circuit, a dormancy control circuit and a battery management system, wherein the charging wake-up circuit comprises a first diode, a second diode, a first resistor, a second resistor and a first capacitor, and the dormancy control circuit comprises a triode, a third resistor and a fourth resistor; one end of a third resistor is used as the input end of the dormancy control circuit and connected to the first output end of the battery management system, the other end of the third resistor is connected to the base electrode of the triode, the collector electrode of the triode is used as the output end of the dormancy control circuit and connected to the cathode of the second diode, the emitter electrode of the triode is grounded, one end of a fourth resistor is connected to the other end of the third resistor, and the other end of the fourth resistor is grounded. The method and the device ensure that the battery management system is awakened normally to realize the charging function during charging, and the battery management system continues to enter the sleep mode after charging is completed, so that extra electric energy is not consumed.

Description

Charging control circuit

Technical Field

The utility model relates to the technical field of power electronics, in particular to a charging control circuit.

Background

The whole electric vehicle controller is a core device for vehicle management, and the controller has various functions of vehicle driving management. The vehicle control unit consists of a power module, a main chip and various driving chips.

The domestic existing electric vehicle charging System meets the requirements of an electric vehicle conduction charging System, in the charging process of the electric vehicle, power supply equipment supplies power to the electric vehicle through a vehicle interface, and when the electric vehicle is stopped and charged, a Battery Management System (BMS) needs to be awakened for normal charging; after full charge, if the BMS continues to maintain an operating state, the amount of power of the 12V system battery will be consumed, resulting in power feeding and energy waste of the 12V system battery; therefore, when the power battery pack is fully charged, it is desirable that the BMS enter a sleep state to ensure the minimum power consumption.

SUMMERY OF THE UTILITY MODEL

An object of an embodiment of the present invention is to provide a charging control circuit, which can continuously enter a sleep state after charging is completed without consuming additional electric energy, while improving EMC (electromagnetic Compatibility) anti-interference performance of a BMS through mutual cooperation between a charging wake-up circuit, a sleep control circuit, and a battery management system.

In order to achieve the above purpose, the embodiment of the present invention adopts the following technical solutions:

according to an aspect of the present invention, there is provided a charge control circuit, including a charge wake-up circuit, a sleep control circuit and a battery management system, wherein the charge wake-up circuit includes a first diode, a second diode, a first resistor, a second resistor and a first capacitor, and the sleep control circuit includes a triode, a third resistor and a fourth resistor;

the anode of the first diode is used as the input end of the charge wake-up circuit and connected to the output end of the external power supply control circuit, the cathode of the first diode is connected to one end of a first resistor, the other end of the first resistor is connected to the anode of a second diode, the cathode of the second diode is connected to one end of a second resistor, the other end of the second resistor is connected to one end of a first capacitor, the other end of the first capacitor is grounded, and the other end of the second resistor is used as the output end of the charge wake-up circuit and connected to the first input end of the battery management system;

one end of a third resistor is used as the input end of the dormancy control circuit and connected to the first output end of the battery management system, the other end of the third resistor is connected to the base electrode of the triode, the collector electrode of the triode is used as the output end of the dormancy control circuit and connected to the cathode of the second diode, the emitter electrode of the triode is grounded, one end of a fourth resistor is connected to the other end of the third resistor, and the other end of the fourth resistor is grounded.

In some embodiments, the charge wake-up circuit further comprises a fifth resistor;

one end of the fifth resistor is connected to the cathode of the first diode, and the other end of the fifth resistor is grounded.

In some embodiments, the charge wake-up circuit further comprises a second capacitor and a third capacitor;

one end of the second capacitor is connected to the cathode of the first diode, the other end of the second capacitor is grounded, one end of the third capacitor is connected to the one end of the fifth resistor, and the other end of the third capacitor is grounded.

In some embodiments, the charge wake-up circuit further comprises a zener diode;

the cathode of the zener diode is connected to the one end of the first capacitor, and the anode of the zener diode is connected to the other end of the first capacitor.

In some embodiments, the charging control circuit further comprises a charging current detection circuit, wherein the charging current detection circuit comprises a sixth resistor, a seventh resistor and a first field effect transistor;

one end of the sixth resistor is connected to the cathode of the first diode, the other end of the sixth resistor is connected to the grid electrode of the first field effect transistor, the drain electrode of the first field effect transistor is connected to one end of the seventh resistor, the source electrode of the first field effect transistor is grounded, and the other end of the seventh resistor is connected to the first output end of the battery management system.

In some embodiments, the charging control circuit further comprises a charging start circuit, and the charging start circuit comprises an eighth resistor, a ninth resistor, a tenth resistor, an eleventh resistor and a second field effect transistor;

one end of an eighth resistor is connected to the cathode of the first diode as the output end of the charging starting circuit, the other end of the eighth resistor is connected to the drain electrode of the second field effect transistor, the source electrode of the second field effect transistor is grounded, the grid electrode of the second field effect transistor is connected to one end of a ninth resistor, the other end of the ninth resistor is grounded, one end of a tenth resistor is connected to one end of a ninth resistor, the other end of the tenth resistor is connected to one end of an eleventh resistor, the other end of the eleventh resistor is grounded, and the other end of the eleventh resistor is connected to the second output end of the battery management system as the input end of the charging starting circuit.

In some embodiments, the charge initiation circuit further comprises a fourth capacitor;

one end of the fourth capacitor is connected to the one end of the ninth resistor, and the other end of the fourth capacitor is grounded.

In some embodiments, a battery management system includes a control chip;

and a wake-up pin of the control chip is connected to the other end of the second resistor as a first input end of the battery management system, a current detection pin of the control chip is connected to one end of the seventh resistor as a second input end of the battery management system, and a control output pin of the control chip is connected to the other end of the eleventh resistor as a second output end of the battery management system.

In some embodiments, the battery management system further comprises a power chip;

and the output end of the power supply chip is used as a first output end of the battery management system and is connected to the other end of the seventh resistor.

In some embodiments, the output of the power supply chip is connected to the power supply port of the control chip to provide power for the control chip.

Compared with the prior art, the utility model has the following beneficial effects:

the application provides a charging control circuit awakens up the back at the realization to BMS, can guarantee that BMS can continue to get into the dormant state after the completion of charging to reduce power consumption.

Additional features and advantages of the utility model will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by the practice of the embodiments of the utility model. The objectives and other advantages of the utility model will be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present invention and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained according to the drawings without inventive efforts.

Fig. 1 shows a schematic diagram of a charging connection signal wake-up circuit provided by a prior art embodiment.

Fig. 2 is a schematic diagram illustrating a scenario in which the charge control circuit according to the embodiment of the present invention is applied.

Fig. 3 shows a first schematic diagram of a charge control circuit according to an embodiment of the present invention.

Fig. 4 shows a second schematic diagram of the charge control circuit according to the embodiment of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments.

Thus, the following detailed description of the embodiments of the present invention, presented in the figures, is not intended to limit the scope of the utility model, as claimed, but is merely representative of selected embodiments of the utility model. All other embodiments, which can be derived by a person skilled in the art from the embodiments of the present invention without making any creative effort, shall fall within the protection scope of the present invention.

It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it need not be further defined and explained in subsequent figures.

Before this application, reference is made to fig. 1, which is a schematic diagram of a wake-up circuit for a charging connection signal provided in the prior art. As shown in fig. 1, when a charging gun is plugged into an electric vehicle, which is equivalent to the closing of a switch K101, a circuit is formed by a power supply V101 in an electric vehicle system through resistors R101, R106, D101, R110 and K101, R110 is adjustable according to the rated capacity of a charging cable, when K101 is closed, a capacitor C101 discharges through R106, D101 and R110, and a triode Q101 discharges through R102, R106, D101 and R110 due to the existence of a collector junction capacitor, so that the voltage at point A, B gradually decreases (the voltage at point B decreases slower than that at point a due to the existence of R102); when the voltage of the point B is smaller than the saturated conducting voltage of the PNP triode Q101, the Q101 is started, an internal power supply V101 of the electric automobile system charges a capacitor branch C102 through the Q101 through a resistor R103, and when the voltage of the cathode of a voltage stabilizing diode D102 is larger than 2.6V, the BMS is awakened through an IO4_ awakening pin; after the capacitor C101 and the collector junction capacitor of the PNP triode Q101 are discharged after a period of time, the internal power supply V101 of the electric automobile system charges the capacitor C101 through the resistor R101 and charges the collector junction capacitor of the PNP triode Q101 through the resistor R101 and the resistor R102, the voltage at the point A, B gradually rises and is finally stable, the voltage at the point B rises in the rising process to enable the voltage at the point B to be larger than the saturated conduction voltage of the PNP triode Q101 to enable the PNP triode Q101 to be closed, the IO4_ wake-up level is finally changed into the low level, and when a sleep command is given to the BMS, the BMS can enter the sleep state again. In addition, when the BMS awakens, the output voltage of the 5V power supply V102 in the BMS provides the detection voltage for the detection point 3, and the NPN triode Q102 is controlled to be turned on to pull down the voltage at the point C to 0V, so as to ensure that the voltage at the point D is suddenly lower than the voltage at the point C because the BMS is 0V after entering the sleep mode when the charging gun is not pulled out after the vehicle is fully charged, thereby triggering the voltage at the point B to enter the circular discharging and charging mode, and then the IO4_ awakening pin also can be in the circular sleep mode and awaken.

The key of the wake-up circuit in the prior art for realizing high-level wake-up and then entering low level is that a switch K101 is closed to form a loop, and a capacitor C101 discharges to form a voltage difference so as to conduct a PNP triode Q101 to obtain high level; the capacitor C101 is charged to reduce the pressure difference, the PNP triode Q101 is closed to enable the IO4_ wake-up pin to form a low level, the capacitor can be charged and discharged by pulses formed by an electromagnetic field in the process of periodic change, the BMS is woken up abnormally, energy waste of a 12-volt battery in a power supply system in a vehicle is caused, and the circuit is simulated, the result shows that the high level 2.6V can be reached in about 50 microseconds, 3 groups of tests show that the sleep is woken up abnormally in the process of the electromagnetic compatibility sleep anti-interference capability test, the pulse action time is longer than 50 microseconds through analysis, the duty ratio is small enough (namely the charging time is short and the discharging time is long), and the sleep is woken up abnormally.

The scheme provided by the utility model mainly relates to the technical field of electric automobile charging, and can be applied to an electric automobile charging scene meeting the requirements of an electric automobile conduction charging system, as shown in fig. 2, the scheme is a scene schematic diagram applicable to a charging control circuit provided by the embodiment of the application, and the application scene can comprise a power supply device, a power supply interface, a vehicle interface and an electric automobile.

The power supply device is connected with the vehicle interface through an alternating current cable L1, an alternating current cable L2, an alternating current cable L3, a neutral line N, a grounding cable PE, a CP signal (Control Pilot Control signal) and a CC signal (Connection configuration charging Connection signal) through a power supply interface, the power supply interface comprises a power supply socket and a power supply plug, the vehicle interface comprises a vehicle socket and a vehicle plug, the power supply socket is arranged on the power supply device, and the vehicle socket is arranged on the electric vehicle. The CC signal and the PE are pure resistance, before the power supply equipment is connected with the vehicle interface, the switch S1 is connected to the +12V power input end of the power supply control device, after the power supply equipment is connected with the vehicle interface, the switch S1 is connected to the PWM end of the power supply control device, namely the CP signal is input into the PWM signal, the state of the power supply control device can be judged by detecting the voltage value of the point 1, and the power supply control device is internally provided with a residual current protector.

After the charging gun is inserted into a vehicle interface, namely the switch S3 is closed, the resistor R4 is short-circuited, whether a CC signal meets requirements or not is judged by comparing voltage values of the detection point 3, the cable power supply capacity of the power supply equipment is judged, the CC signal meets the requirements, the BMS in the vehicle control device is awakened, meanwhile, the BMS determines the output power of the charging equipment by detecting the duty ratio of a PWM signal input to the detection point 2, after the configuration is completed, the BMS controls the switch S2 to be closed through the resistor R2, simultaneously sends a signal to the power supply equipment, controls the switches K1 and K2 in the power supply equipment to be closed successively, and the power supply equipment charges the electric vehicle through a vehicle-mounted charger in the electric vehicle.

The utility model provides a charging control circuit, which is shown in fig. 3 and is a schematic diagram of the charging control circuit provided by the embodiment of the utility model.

As shown in fig. 3, the charge control circuit includes: the charge wake-up circuit 100 includes a first diode CP _ D1, a second diode CP _ D2, a first resistor CP _ R1, a second resistor CP _ R2, and a first capacitor CP _ C1, the sleep control circuit 200 includes a transistor CP _ Q1, a third resistor CP _ R3, and a fourth resistor CP _ R4, and the battery management system 300.

An anode of the first diode CP _ D1 is connected to an output terminal of the external power supply control circuit as an input terminal of the charge wake-up circuit 100, a cathode of the first diode CP _ D1 is connected to one end of a first resistor CP _ R1, the other end of the first resistor CP _ R1 is connected to an anode of a second diode CP _ D2, a cathode of the second diode CP _ D2 is connected to one end of a second resistor CP _ R2, the other end of the second resistor CP _ R2 is connected to one end of a first capacitor CP _ C1, the other end of the first capacitor CP _ C1 is grounded, and the other end of the second resistor CP _ R2 is connected to a first input terminal of the battery management system 300 as an output terminal of the charge wake-up circuit.

One end of the third resistor CP _ R3 is connected to the first output terminal of the battery management system 300 as the input terminal of the sleep control circuit 200, the other end of the third resistor CP _ R3 is connected to the base of the transistor CP _ Q1, the collector of the transistor CP _ Q1 is connected to the cathode of the second diode CP _ D2 as the output terminal of the sleep control circuit 200, the emitter of the transistor CP _ Q1 is grounded, one end of the fourth resistor CP _ R4 is connected to the other end of the third resistor CP _ R3, and the other end of the fourth resistor CP _ R4 is grounded.

In a preferred embodiment, the charge wake-up circuit 100 may further include a fifth resistor (not shown), one end of the fifth resistor is connected to the cathode of the first diode, and the other end of the fifth resistor is grounded.

In the embodiment of the present invention, the first diode CP _ D1 is equivalent to the diode D1 in fig. 2, the anode of the first diode CP _ D1 is used as the input terminal of the charge-wake-up circuit 100 and is connected to the CP signal interface in fig. 2, the power supply device provides the PWM signal to the input terminal of the charge-wake-up circuit 100 through the internal power supply control device, that is, as shown in fig. 2 and fig. 3, after the power supply device is successfully connected through the vehicle interface, the switch S1 is connected to the PWM terminal, the PWM signal is input to the input terminal of the charge-wake-up circuit 100 through the CP signal interface, the PWM signal charges the first capacitor CP _ C1 through the second diode CP _ D2, the first resistor CP _ R1 and the second resistor CP _ R2, the voltage value of the output terminal of the charge-wake-up circuit gradually increases, the battery management system 300 detects the voltage value of the output terminal of the charge-wake-up circuit, when the voltage at the point is greater than 2.6v, the battery management system 300 is awakened, and when the battery management system 300 is awakened, the battery management system 300 outputs a high level signal to the sleep control circuit 200.

The transistor CP _ Q1 in the sleep control circuit 200 is an NPN transistor, the base of the transistor CP _ Q1 receives a high level signal, and then is turned on through the voltage division of the third resistor CP _ R3 and the fourth resistor CP _ R4, and outputs a low level signal at the collector of the transistor CP _ Q1, so that the wake-up signal of the battery management system 300 is pulled down to 0V, and the battery management system 300 keeps a low level after waking up, and when the power battery pack is fully charged, the battery management system 300 can continue to enter a sleep state when receiving a sleep command of the vehicle controller.

Referring to fig. 4, which is a schematic diagram of a second charging control circuit according to an embodiment of the present invention, referring to fig. 4, the charging wake-up circuit 100 further includes a fifth resistor CP _ R5, one end of the fifth resistor CP _ R5 is connected to the cathode of the first diode CP _ D1, and the other end of the fifth resistor CP _ R5 is grounded.

Referring to fig. 2 and 4, the fifth resistor CP _ R5 is equivalent to the resistor R3 in fig. 2, the input PWM signal forms a voltage division through the resistor R1 and the fifth resistor CP _ R5, and the voltage value detected at the detection point 1 decreases, indicating that the switch S1 is normally closed.

The charge wake-up circuit 100 further includes a second capacitor CP _ C2 and a third capacitor CP _ C3, one end of the second capacitor CP _ C2 is connected to the cathode of the first diode CP _ D1, the other end of the second capacitor CP _ C2 is grounded, one end of the third capacitor CP _ C3 is connected to one end of the fifth resistor CP _ R5, and the other end of the third capacitor CP _ C3 is grounded. Here, the second capacitor CP _ C2 and the third capacitor CP _ C3 function as filter capacitors to exclude signal interference in the circuit.

In a preferred embodiment, the charge wake-up circuit 100 may further include a zener diode CP _ D3, a cathode of the zener diode CP _ D3 is connected to one end of the first capacitor CP _ C1, and an anode of the zener diode CP _ D3 is connected to the other end of the first capacitor CP _ C1. The zener diode CP _ D3 functions to stabilize the voltage at 5V and protect the 5V power supply inside the battery management system 300.

In a preferred embodiment, the charging control circuit further includes a charging current detection circuit 400, the charging current detection circuit 400 includes a sixth resistor CP _ R6, a seventh resistor CP _ R7 and a first fet CP _ NMOS1, one end of the sixth resistor CP _ R6 is connected to the cathode of the first diode CP _ D1, the other end of the sixth resistor CP _ R6 is connected to the gate CP _ NMOS1 of the first fet, the drain of the first fet CP _ NMOS1 is connected to one end of the seventh resistor CP _ R7, the source of the first fet CP _ NMOS1 is grounded, and the other end of the seventh resistor CP _ R7 is connected to the first output terminal of the battery management system 300.

The battery management system 300 includes a control chip 301, a wake-up pin of the control chip 301 is connected to the other end of the second resistor CP _ R2 as a first input terminal of the battery management system 300, and a current detection pin of the control chip 301 is connected to one end of a seventh resistor as a second input terminal of the battery management system 300.

In an alternative embodiment, the battery management system 300 further includes a power chip 302, and an output terminal of the power chip 302 is connected to the other terminal of the seventh resistor as a first output terminal of the battery management system 300.

The output of the power chip 302 is connected to the power supply port of the control chip to provide power for the control chip.

In the embodiment of the present invention, after the battery management system 300 is woken up, the power chip 302 of the battery management system 300 outputs a 5V voltage to provide a signal source to the charging current detection circuit 400 through the other end of the seventh resistor CP _ R7, when the first output end of the battery management system 300 outputs a high level, the first fet CP _ NMOS1 is turned on, the voltage at one end of the seventh resistor CP _ R7 is pulled down to 0V (low level), when the power chip 302 outputs a low level, the first fet CP _ NMOS1 is turned on, the voltage at one end of the seventh resistor CP _ R7 is kept at 5V (high level), and the duty ratio, i.e., the charging current, is obtained through the periodic variation of the voltage at one end of the seventh resistor CP _ R7.

Referring to fig. 4, in a preferred embodiment, the charge control circuit may further include a charge starting circuit 500, and the charge starting circuit 500 includes an eighth resistor CP _ R8, a ninth resistor CP _ R9, a tenth resistor CP _ R10, an eleventh resistor CP _ R11, and a second fet CP _ NMOS 2.

Specifically, one end of the eighth resistor CP _ R8 is connected to the cathode of the first diode CP _ D1 as the output terminal of the charge starting circuit 500, the other end of the eighth resistor CP _ R8 is connected to the drain of the second fet CP _ NMOS2, the source of the second fet CP _ NMOS2 is grounded, the gate of the second fet CP _ NMOS2 is connected to one end of the ninth resistor CP _ R9, the other end of the ninth resistor CP _ R9 is grounded, one end of the tenth resistor CP _ R10 is connected to the one end of the ninth resistor CP _ R9, the other end of the tenth resistor CP _ R10 is connected to one end of the eleventh resistor CP _ R11, the other end of the eleventh resistor CP _ R11 is grounded, and the other end of the eleventh resistor CP _ R11 is connected to the second output terminal of the battery management system 300 as the input terminal of the charge starting circuit 500.

A control output pin of the control chip 301 is connected as a second output terminal of the battery management system 300 to the other end of the eleventh resistor.

In the embodiment of the application, after the battery management system 300 is awakened, the vehicle-mounted charger and the power supply device perform self-checking normally and then send a control instruction to the battery management system 300, and the battery management system 300 controls the second field-effect transistor CP _ NMOS2 (i.e., the second switch S2) to be turned on, so that the vehicle can be charged; after the charging is completed, the battery management system 300 controls the second fet CP _ NMOS2 (i.e., the second switch S2) to be turned off, and the vehicle exits the charging state.

Referring to fig. 4, the charge start circuit 500 further includes a fourth capacitor CP _ C4, one end of the fourth capacitor CP _ C4 is connected to the one end of the ninth resistor CP _ R9, and the other end of the fourth capacitor CP _ C4 is grounded.

The utility model discloses a charging control circuit, which comprises a charging wake-up circuit, a dormancy control circuit and a battery management system, wherein the circuit for waking up the battery management system by using a CP voltage signal only has the charging wake-up circuit in the prior art, so that a wake-up pin can always keep a high level after the battery management system wakes up, and after a battery pack is fully charged, a vehicle control unit sends a dormancy command to the battery management system, the battery management system cannot normally enter a dormancy state because the wake-up pin always keeps the high level, so that a battery is always in a feed state, energy waste is caused, and the service life of the 12V battery is shortened.

The charging control circuit is awakened by external voltage, avoids the interference of a battery system in the vehicle environment, is not influenced by an electromagnetic field and relevant pulses, and immediately enters a low level state after the BMS is awakened, so that the charging control circuit can continuously enter a dormant state after the charging is finished, and the electric energy is saved.

It should be noted that, in this document, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.

Finally, it should be noted that: although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art will understand that: any person skilled in the art can modify or easily conceive the technical solutions described in the foregoing embodiments or equivalent substitutes for some technical features within the technical scope of the present disclosure; such modifications, changes or substitutions do not depart from the spirit and scope of the embodiments of the present invention, and they should be construed as being included therein. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. A charging control circuit is characterized by comprising a charging wake-up circuit, a dormancy control circuit and a battery management system, wherein the charging wake-up circuit comprises a first diode, a second diode, a first resistor, a second resistor and a first capacitor, and the dormancy control circuit comprises a triode, a third resistor and a fourth resistor;

2. The charge control circuit of claim 1, wherein the charge wake-up circuit further comprises a fifth resistor;

3. The charge control circuit of claim 2, wherein the charge wake-up circuit further comprises a second capacitor and a third capacitor;

4. The charge control circuit of claim 1, wherein the charge wake-up circuit further comprises a zener diode;

5. The charge control circuit according to claim 1, wherein the charge control circuit further comprises a charge current detection circuit, the charge current detection circuit comprising a sixth resistor, a seventh resistor and a first field effect transistor;

6. The charge control circuit according to claim 1, further comprising a charge start circuit, wherein the charge start circuit comprises an eighth resistor, a ninth resistor, a tenth resistor, an eleventh resistor, and a second fet;

7. The charge control circuit of claim 6, wherein the charge start circuit further comprises a fourth capacitor;

8. The charge control circuit of claim 5, wherein the battery management system comprises a control chip;

9. The charge control circuit of claim 8, wherein the battery management system further comprises a power chip;

10. The charge control circuit of claim 9, wherein the output terminal of the power chip is connected to the power supply port of the control chip to supply power to the control chip.