Battery control circuit, power supply device, electric vehicle

Abstract

The application relates to the battery technical field and discloses a battery control circuit, a power supply device and an electric vehicle, wherein the control circuit comprises a controller and at least two charge-discharge control modules; each charge-discharge control module is used for connecting a corresponding battery pack; each charge-discharge control module comprises a discharge control switch, a bypass control switch and a current sampling unit; the positive electrode end of the battery pack, the bypass control switch, the discharge control switch and the negative electrode end of the battery pack are sequentially connected; the current sampling unit is connected with the battery pack and is used for acquiring a charge-discharge current signal of the battery pack; the bypass control switches in the charge-discharge control modules are arranged in series; the controller is used for determining a charge-discharge state of the battery pack according to the charge-discharge current signal; when the battery pack is charged to a full-electricity state, the bypass control switch is turned on; when the battery pack is discharged to a low-electricity state, the discharge control switch is turned off and the bypass control switch is turned on.

Description

Technical Field

[0001] This application relates to the field of battery technology, and in particular to a battery control circuit, a power supply device, and an electric vehicle. Background Technology

[0002] With the rapid development of electric vehicle technology, series battery systems have been widely used in the electric vehicle field due to their advantages such as simple structure and low cost. In a series battery system, multiple battery packs are connected in series to provide a common power source for the electric vehicle. This connection method allows the current to form a unified loop between the battery packs, thereby achieving centralized output of electrical energy.

[0003] However, in actual operation, different battery packs may exhibit inconsistent charging and discharging performance due to differences in manufacturing processes, usage time, or changes in ambient temperature. When one of the battery packs malfunctions or runs out of power, it creates an open circuit, cutting off the current flow in the entire series circuit. This prevents the entire battery system from continuing to provide power to the electric vehicle, severely impacting its continuous operation capability. Utility Model Content

[0004] In view of this, embodiments of this application provide a battery control circuit, a power supply device, and an electric vehicle, which can effectively solve the problem in the prior art where a battery pack in an electric vehicle malfunctions or runs out of power, resulting in the battery system being unable to provide power to the electric vehicle.

[0005] In a first aspect, embodiments of this application provide a battery control circuit, the control circuit including a controller and at least two charge / discharge control modules; Each of the charge / discharge control modules is used to connect to the corresponding battery pack; Each of the charging and discharging control modules includes: a discharge control switch, a bypass control switch, and a current sampling unit. The positive terminal of the battery pack, the bypass control switch, the discharge control switch, and the negative terminal of the battery pack are connected in sequence. The current sampling unit is connected to the battery pack and is used to acquire the charging and discharging current signal of the battery pack. The bypass control switches in each of the charging and discharging control modules are connected in series. The controller is electrically connected to the control terminal of each current sampling unit, each discharge control switch and each bypass control switch, respectively. The controller is used to determine the charging and discharging state of the battery pack based on the charging and discharging current signal. When the battery pack is fully charged, the bypass control switch is turned on; when the battery pack is discharged to a low charge level, the discharge control switch is turned off and the bypass control switch is turned on.

[0006] In some embodiments, the charge / discharge control module further includes an interlock unit, the input terminal of which is electrically connected to the controller, the first output terminal of which is connected to the control terminal of the bypass control switch, and the second output terminal of which is connected to the control terminal of the discharge control switch. In response to the first conduction signal of the controller, the interlock unit controls the discharge control switch to turn off and then controls the bypass control switch to turn on. In response to the first shutdown signal from the controller, the interlock unit controls the bypass control switch to turn off and then controls the discharge control switch to turn on.

[0007] In some embodiments, the interlocking unit includes: a first interlocking switch, a second interlocking switch, a first interlocking control subunit, a second interlocking control subunit, a first pressure dividing subunit, and a second pressure dividing subunit; The first interlock control subunit is connected between the controller and the control terminal of the first interlock switch. The first terminal of the first interlock switch is connected to the other terminal of the first voltage divider subunit, and the second terminal of the first interlock switch is grounded. One terminal of the first voltage divider subunit is connected to the positive terminal of the battery pack, and the voltage divider node of the first voltage divider subunit is connected to the control terminal of the bypass control switch. The second interlock control subunit is connected between the controller and the control terminal of the second interlock switch. The first terminal of the second interlock switch is connected to the series node of the second voltage divider subunit, and the second terminal of the second interlock switch is grounded. One end of the second voltage divider subunit is electrically connected to the controller, and the other end of the second voltage divider subunit is connected to the negative terminal of the battery pack. The voltage divider node of the second voltage divider subunit is connected to the control terminal of the discharge control switch.

[0008] In some embodiments, the first interlock control subunit includes a first resistor and a first capacitor. One end of the first resistor is electrically connected to the controller, the other end of the first resistor is connected to the first terminal of the first capacitor, the first terminal of the first capacitor is connected to the control terminal of the first interlock switch, and the second terminal of the first capacitor is connected to the second terminal of the first interlock switch. The second interlock control subunit includes a second resistor and a second capacitor. One end of the second resistor is electrically connected to the controller, and the other end of the second resistor is connected to the first end of the second capacitor. The first end of the second capacitor is electrically connected to the control terminal of the second interlock switch, and the second end of the second capacitor is connected to the second terminal of the second interlock switch. The resistance value of the second resistor is less than the resistance value of the first resistor.

[0009] In some embodiments, the first interlock control subunit further includes a first diode and a third resistor, one end of the third resistor is connected to the first terminal of the first capacitor, the other end of the third resistor is connected to the positive terminal of the first diode, and the negative terminal of the first diode is electrically connected to the controller. The second interlock control subunit further includes a second diode and a fourth resistor. The positive terminal of the second diode is electrically connected to the controller, and the negative terminal of the second diode is connected to one end of the second resistor. One end of the fourth resistor is connected to the first terminal of the second capacitor, and the other end of the fourth resistor is electrically connected to the controller. The resistance value of the third resistor is less than that of the fourth resistor.

[0010] In some embodiments, the second interlock control subunit further includes a comparator, the non-inverting input of which is connected to the first terminal of the second capacitor, the inverting input of which is used to input a first power supply signal, and the output of which is connected to the control terminal of the second interlock switch.

[0011] In some embodiments, the current sampling unit includes a sampling resistor, a third voltage divider unit, a fourth voltage divider unit, and an operational amplifier. One end of the sampling resistor is connected to the first terminal of the bypass control switch, and the other end of the sampling resistor serves as one end of the charge / discharge control module. One end of the third voltage divider unit is connected to one end of the sampling resistor, and the voltage divider node of the third voltage divider unit is connected to the non-inverting input terminal of the operational amplifier. The other end of the third voltage divider unit is used to input a second power supply signal. One end of the fourth voltage divider unit is connected to the other end of the sampling resistor. The voltage divider node of the fourth voltage divider unit is connected to the inverting input terminal of the operational amplifier. The other end of the fourth voltage divider unit is connected to the output terminal of the operational amplifier. The output terminal of the operational amplifier is electrically connected to the controller. The power supply terminal of the operational amplifier is used to input a third power supply signal, and the second power supply signal is smaller than the third power supply signal.

[0012] In some embodiments, the bypass control switch includes a switching transistor, a first end of which is connected to the positive terminal of the battery pack, a second end of which is connected to the first terminal of the discharge control switch, and a control terminal of which is electrically connected to the controller.

[0013] Secondly, embodiments of this application provide a power supply device, which includes a plurality of battery packs and at least one battery control circuit as described in the first aspect above, wherein each of the battery packs is connected to a corresponding charge and discharge control module.

[0014] Thirdly, embodiments of this application provide an electric vehicle, which includes the power supply device described in the second aspect above.

[0015] The embodiments of this application have the following beneficial effects: The control circuit of this application includes a controller and at least two charge / discharge control modules. Each charge / discharge control module is used to connect to a corresponding battery pack. Each charge / discharge control module includes a discharge control switch, a bypass control switch, and a current sampling unit. The positive terminal of the battery pack, the bypass control switch, the discharge control switch, and the negative terminal of the battery pack are connected in sequence. The current sampling unit is connected to the battery pack and is used to acquire the charge / discharge current signal of the battery pack. The bypass control switches in each charge / discharge control module are connected in series. The controller is electrically connected to the control terminals of each current sampling unit, each discharge control switch, and each bypass control switch. The controller is used to determine the charge / discharge state of the battery pack based on the charge / discharge current signal. When the battery pack is fully charged, the bypass control switch is turned on. When the battery pack is discharged to a low charge state, the discharge control switch is turned off and the bypass control switch is turned on. This application obtains current through a controller to determine whether the battery pack is fully charged or low-charged. If it is fully charged, the bypass control switch of the battery pack is turned on; if it is low-charged, the discharge control switch of the battery pack is turned off and the bypass control switch is turned on, so that other battery packs can continue to work through the bypass of the battery pack, thereby maintaining the continuous operation of the entire series system, continuously providing power to the electric vehicle, and ensuring the stability and reliability of the system. Attached Figure Description

[0016] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 A schematic diagram of the battery control circuit according to an embodiment of this application is shown; Figure 2 A schematic diagram of a first application of the battery control circuit according to an embodiment of this application is shown; Figure 3 A second application schematic diagram of the battery control circuit according to an embodiment of this application is shown; Figure 4 A schematic diagram of the charge / discharge control module according to an embodiment of this application is shown; Figure 5 A circuit diagram of the charge / discharge control module according to an embodiment of this application is shown.

[0018] Explanation of key component symbols: 10: Controller; 20: Charge / discharge control module; 211: Battery pack; 212: Discharge control switch; 221: Bypass control switch; 23: Current sampling unit; 231: Third voltage divider subunit; 232: Fourth voltage divider subunit; 24: Interlock unit; 241: First interlock control subunit; 242: Second interlock control subunit; 243: First voltage divider subunit; 244: Second voltage divider subunit; 30: Load; 40: Charger. Detailed Implementation

[0019] The technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments.

[0020] The components of the embodiments of this application described and illustrated in the accompanying drawings can be arranged and designed in a variety of different configurations. Therefore, the following detailed description of the embodiments of this application provided in the drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0021] In the following text, the terms "comprising," "having," and their cognates, which may be used in various embodiments of this application, are intended only to indicate a particular feature, number, step, operation, element, component, or combination thereof, and should not be construed as primarily excluding the presence of one or more other features, numbers, steps, operations, elements, components, or combinations thereof, or adding the possibility of one or more combinations thereof. Furthermore, the terms "first," "second," "third," etc., are used only for distinguishing descriptions and should not be construed as indicating or implying relative importance.

[0022] Unless otherwise specified, all terms used herein (including technical and scientific terms) shall have the same meaning as commonly understood by one of ordinary skill in the art to which the various embodiments of this application pertain. Terms (such as those defined in commonly used dictionaries) shall be interpreted as having the same meaning as in their contextual meaning in the relevant technical field and shall not be construed as having an idealized or overly formal meaning, unless clearly defined in the various embodiments of this application.

[0023] The following detailed description of some embodiments of this application is provided in conjunction with the accompanying drawings. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0024] In view of the problems in existing electric vehicles, such as the battery system being unable to provide power to the electric vehicle due to a malfunction or depletion of a battery pack, this application provides a battery control circuit, a power supply device, and an electric vehicle. This application obtains current through a controller to determine whether the battery pack is fully charged or low-charged. If it is fully charged, the bypass control switch for that battery pack is activated; if it is low-charged, the discharge control switch for that battery pack is deactivated, and the bypass control switch is activated, allowing other battery packs to continue operating through the bypass of that battery pack. This maintains the continuous operation of the entire series system, continuously providing power to the electric vehicle and ensuring the stability and reliability of the system.

[0025] The battery control circuit will be described below with reference to some specific embodiments.

[0026] Figure 1 A schematic diagram of a battery control circuit according to an embodiment of this application is shown.

[0027] It is understood that the battery control circuit of this application can be located inside the battery, or it can be located independently of the battery. Exemplarily, the battery control circuit of this application is located inside the lithium battery. The lithium battery of this application can power any kind of electrical device. Exemplarily, the lithium battery of this application is a lithium battery for two-wheeled vehicles or a lithium battery for three-wheeled vehicles, used for charging two-wheeled vehicles or three-wheeled vehicles. Exemplarily, the battery control circuit includes a controller 10 and at least two charge / discharge control modules 20. This application takes two charge / discharge control modules 20 as an example. It is understood that the control circuit of this application can be configured to connect any number of charge / discharge control modules 20 in series. Each charge / discharge control module 20 has the same structure, including a discharge control switch 212, a bypass control switch 221, and a current sampling unit 23. The positive terminal of the battery pack 211, the bypass control switch 221, the discharge control switch 212, and the negative terminal of the battery pack 211 are connected in sequence. Specifically, the positive terminal of the battery pack 211 is connected to the first terminal of the bypass control switch 221, the second terminal of the bypass control switch 221 is connected to the first terminal of the discharge control switch 212, and the second terminal of the discharge control switch 212 is connected to the negative terminal of the battery pack 211. The bypass control switches 221 in each charge and discharge control module 20 are connected in series.

[0028] Each current sampling unit 23 is used to acquire the charging and discharging current signal of each battery pack 211. Specifically, the current sampling unit 23 can be a sampling resistor or a current sensor. Furthermore, while setting the sampling resistor, an operational amplifier can also be set to process the signal of the sampling resistor to improve the accuracy of current sampling. It is understood that if the current sampling unit 23 is a sampling resistor, the sampling resistor should be set at the connection between the first terminal of the discharge control switch 212 and the second terminal of the bypass control switch 221. Each charging and discharging control module 20 is connected in series with the current sampling unit 23 through the corresponding bypass control switch 221.

[0029] Understandably, the discharge control switch 212 and bypass control switch 221 can be configured according to the actual application. For example, the discharge control switch 212 and bypass control switch 221 can be configured as switching transistors, relays, or optocouplers. The structures of the discharge control switch 212 and bypass control switch 221 can be the same or different. For example, the bypass control switch 221 is a switching transistor. The first end of the switching transistor is connected to the positive terminal of the battery pack 211, and the second end of the switching transistor is connected to one end of the discharge control switch 212. The control terminal of the switching transistor is electrically connected to the controller 10. By configuring the bypass control switch 221 as a switching transistor, the switching transistor can quickly respond to the control signal of the controller 10, realize timely switching of the bypass state, and improve the intelligence and reliability of the system.

[0030] The controller 10 can be any type of controller, such as an MCU, an FPGA, or a CPU. For example, the controller 10 is composed of an MCU and a front-end analog chip. The MCU is driven by a written software program, and the front-end analog chip is responsible for acquiring voltage and current and transmitting them to the MCU, and controlling each control switch according to the instructions sent by the MCU.

[0031] The controller 10 is electrically connected to the control terminals of each current sampling unit 23, each discharge control switch 212, and each bypass control switch 221. It determines the charging and discharging state of the battery pack 211 based on the charging and discharging current signal and controls each control switch. The controller 10 is used to determine that the current battery pack 211 is fully charged when the charging and discharging current signal of the current battery pack 211 is within a first threshold range; and to determine that the current battery pack 211 is in a low-charge state when the charging and discharging current signal is within a second threshold range. The first threshold range and the second threshold range can be set according to the actual application.

[0032] Specifically, Figure 2This diagram illustrates an application of the battery control circuit according to an embodiment of this application. The battery control circuit supplies power to the load 30. When the battery pack 211 is discharging normally, the controller 10 turns on the discharge control switch 212 corresponding to the battery pack 211, while the bypass control switch 221 is closed. The battery pack 211 discharges through a loop formed by the positive terminal of the battery pack 211 → one end of the charge / discharge control module 20 → all upstream series-connected battery packs → load 30 → all downstream series-connected battery packs → the other end of the charge / discharge control module 20 → discharge control switch 212 → negative terminal of the battery pack 211. During the discharge process, the current sampling unit 23 collects the current signal in the loop and transmits it to the controller 10. When it is determined that the battery pack 211 has discharged to a low charge state, the controller turns off the discharge control switch 212 corresponding to the battery pack 211 and turns on the bypass control switch 221 corresponding to the battery pack 211. The discharge circuit is changed to: one end of the charge / discharge control module 20 → all upstream series-connected battery packs → load 30 → all downstream series-connected battery packs → the other end of the charge / discharge control module 20 → bypass control switch 221. This stops battery pack 211 from discharging, while other battery packs 211 can still continue to operate through the bypass of battery pack 211.

[0033] Figure 3 This diagram illustrates another application of the battery control circuit according to an embodiment of this application. The battery control circuit is powered by a charger 40. When the battery pack 211 is charging normally, a charging loop is formed through the positive terminal of the charger 40 → all upstream series-connected battery packs → one end of the charge / discharge control module 20 → the positive terminal of the battery pack 211 → the internal cells of the battery pack 211 → the negative terminal of the battery pack 211 → the discharge control switch 212 → the other end of the charge / discharge control module 20 → all downstream series-connected battery packs → the negative terminal of the charger 40. During charging, the current sampling unit 23 collects the current signal in the loop and transmits it to the controller 10. When it is determined that the battery pack 211 is fully charged, the bypass control switch 221 corresponding to the battery pack 211 is turned on. The charging circuit is changed to: through the positive terminal of the charger 40 → all upstream series-connected battery packs → one end of the charge / discharge control module 20 → bypass control switch 221 → the other end of the charge / discharge control module 20 → all downstream series-connected battery packs → negative terminal of the charger 40, so that battery pack 211 stops charging, while other battery packs 211 can still continue to be charged through the bypass of battery pack 211.

[0034] In this embodiment, a current sampling unit 23 is used to collect the charging or discharging current of the battery pack 211. The controller 10 then determines whether the battery pack 211 is fully charged or low-charged based on the charging / discharging current signal. If the battery pack 211 is low-charged, the corresponding discharge control switch 212 is turned off, and the corresponding bypass control switch 221 is turned on. If the battery pack 211 is fully charged, the corresponding bypass control switch 221 is turned on. This prevents the battery pack 211 from continuing to operate under extreme conditions, reduces safety risks caused by battery pack 211 malfunctions, and ensures that the battery pack 211 no longer participates in the main circuit's charging and discharging. Other battery packs 211 can still continue to operate through the bypass of this battery pack 211. Even if individual battery packs 211 fail or are not in operation, the system as a whole can still operate normally, improving the system's fault tolerance. Furthermore, by controlling the bypass control switch 221, the battery packs 211 can be dynamically connected or bypassed, allowing the system to be flexibly applied to different voltage platforms such as 48V, 60V, 72V, 84V, and 96V, achieving multi-voltage platform compatibility and flexible expansion.

[0035] In one embodiment, based on the above embodiments, Figure 4 The diagram shows another structural schematic of the charge / discharge control module 20. The charge / discharge control module 20 also includes an interlock unit 24. The input terminal of the interlock unit 24 is electrically connected to the controller 10. The first output terminal of the interlock unit 24 is connected to the control terminal of the bypass control switch 221, and the second output terminal of the interlock unit 24 is connected to the control terminal of the discharge control switch 212. In response to a first turn-on signal from the controller 10, the interlock unit 24 controls the bypass control switch 221 to turn on after the discharge control switch 212 is turned off; in response to a first turn-off signal from the controller 10, the interlock unit 24 controls the discharge control switch 212 to turn on after the bypass control switch 221 is turned off. Interlocking unit 24, through timing control of either "first turning off discharge control switch 212, then turning on bypass control switch 221" or "first turning off bypass control switch 221, then turning on discharge control switch 212," ensures the continuous operation of the entire series system while preventing both control switches from being turned on simultaneously. This prevents the battery cell from forming a short circuit through the two control switches, enhancing the system's fault tolerance and stability. Furthermore, integrating complex control switch switching logic into interlocking unit 24 reduces the burden on controller 10, allowing it to focus on state judgment and strategy formulation, thus improving the system's level of automation control.

[0036] As an alternative solution, Figure 5 The diagram shows a circuit diagram of the charge / discharge control module 20, where P+ represents one end of the charge / discharge control module 20 and P- represents the other end of the charge / discharge control module 20.

[0037] In one embodiment, such as Figure 5 As shown, the interlocking unit 24 includes: a first interlocking switch, a second interlocking switch, a first interlocking control subunit 241, a second interlocking control subunit 242, a first voltage divider subunit 243, and a second voltage divider subunit 244; wherein, the first interlocking control subunit 241 is connected between the controller 10 and the control terminal of the first interlocking switch, the first end of the first interlocking switch is connected to the other end of the first voltage divider subunit 243, the second end of the first interlocking switch is grounded, one end of the first voltage divider subunit 243 is connected to the positive terminal of the battery pack 211, and the voltage divider node of the first voltage divider subunit 243 is connected to the control terminal of the bypass control switch 221.

[0038] The second interlock control subunit 242 is connected between the controller 10 and the control terminal of the second interlock switch. The first terminal of the second interlock switch is connected to the series node of the second voltage divider subunit 244, and the second terminal of the second interlock switch is grounded. One end of the second voltage divider subunit 244 is electrically connected to the controller 10, and the other end of the second voltage divider subunit 244 is connected to the negative terminal of the battery pack 211. The voltage divider node of the second voltage divider subunit 244 is connected to the control terminal of the discharge control switch 212. Exemplarily, as shown... Figure 5 As shown, the first interlock switch is transistor Q3, the second interlock switch is transistor Q4, the discharge control switch 212 is transistor Q1, and the bypass control switch 221 is transistor Q2. The controller 10 only needs to control the on / off state of the interlock switches to control the switching state of the control switches through the interlock unit 24, reducing the control pressure and power consumption of the controller 10 and ensuring its safety. Furthermore, as an intermediate part of the switch control, the interlock switches can prevent erroneous signals from directly affecting the control switches in cases of abnormal controller 10 signals, noise interference, or driver chip failure, thus improving the system's anti-interference capability.

[0039] The first voltage divider subunit 243 includes a first voltage divider resistor Res1 and a second voltage divider resistor Res2. One end of the first voltage divider resistor Res1 is connected to the positive terminal of the battery pack 211, and the other end of the first voltage divider resistor Res1 is connected to the control terminal of the switch Q2. One end of the second voltage divider resistor Res2 is connected to the other end of the first voltage divider resistor Res1, and the other end of the second voltage divider resistor Res2 is connected to the first terminal of the switch Q3. The second voltage divider subunit 244 includes a third voltage divider resistor Res3 and a fourth voltage divider resistor Res4. One end of the third voltage divider resistor Res3 is connected to the controller 10, and the other end of the third voltage divider resistor Res3 is connected to the control terminal of the switch Q1 and one end of the fourth voltage divider resistor Res4. The other end of the fourth voltage divider resistor Res4 is connected to the negative terminal of the battery pack 211, and one end of the fourth voltage divider resistor Res4 is connected to the first terminal of the switch Q4.

[0040] Specifically, in order to achieve the following: when the interlock unit 24 receives the first conduction signal from the controller 10, the control discharge control switch 212 is turned off and the control bypass control switch 221 is turned on, the first interlock control subunit 241 includes a first resistor R1 and a first capacitor C1. One end of the first resistor R1 is electrically connected to the controller 10, and the other end of the first resistor R1 is connected to the first end of the first capacitor C1. The first end of the first capacitor C1 is connected to the control terminal of the switching transistor Q3, and the second end of the first capacitor C1 is connected to the second terminal of the switching transistor Q3. The second interlock control subunit 242 includes a second resistor R2 and a second capacitor C2. One end of the second resistor R2 is electrically connected to the controller 10, and the other end of the second resistor R2 is connected to the first end of the second capacitor C2. The first end of the second capacitor C2 is electrically connected to the control terminal of the switching transistor Q4, and the second end of the second capacitor C2 is connected to the second terminal of the switching transistor Q4.

[0041] The resistance of the second resistor R2 is less than that of the first resistor R1. Exemplarily, the first turn-on signal of the controller 10 is a high-level signal. When the controller 10 outputs the first turn-on signal, the first turn-on signal charges the first capacitor C1 through the first resistor R1 until it is charged to a value greater than the turn-on voltage of the switch Q3, causing the switch Q3 to turn on, thereby controlling the switch Q2 to turn on. Simultaneously, the first turn-on signal charges the second capacitor C2 through the second resistor R2 until it is charged to a value greater than the turn-on voltage of the switch Q4, causing the switch Q4 to turn on, thereby controlling the switch Q1 to turn off. Because the resistance of the first resistor R1 is greater than that of the second resistor R2, the conduction time of the switch Q4 is less than the conduction time of the switch Q3. In the interlocking process, after the controller 10 outputs the first turn-on signal, the interlocking unit 24 first controls the switch Q1 to turn off, and then controls the switch Q2 to turn on. The interlocking control subunit is set as an RC circuit, and the switching sequence control is realized through the hardware RC circuit to ensure the safe switching logic of "turn off first and then turn on", avoid the risk of short circuit, and at the same time simplify the complexity of the logic control of the controller 10 and improve the system response speed. In addition, the delay of the RC circuit realizes a controllable switching action time difference, avoids voltage / current sudden changes during the switching process, and improves the stability and reliability of the system.

[0042] To ensure that when the interlock unit 24 receives the first shutdown signal from the controller 10, the bypass control switch 221 is turned off and the discharge control switch 212 is turned on, the first interlock control subunit 241 further includes a first diode D1 and a third resistor R3. One end of the third resistor R3 is connected to the first terminal of the first capacitor C1, and the other end of the third resistor R3 is connected to the positive terminal of the first diode D1. The negative terminal of the first diode D1 is electrically connected to the controller 10. The second interlock control subunit 242 further includes a second diode D3 and a fourth resistor R4. The positive terminal of the second diode D2 is electrically connected to the controller 10, and the negative terminal of the second diode D2 is connected to one end of the second resistor R2. One end of the fourth resistor R4 is connected to the first terminal of the second capacitor C2, and the other end of the fourth resistor R4 is electrically connected to the controller 10.

[0043] The resistance of the third resistor R3 is less than that of the fourth resistor R4. Exemplarily, the first turn-off signal of the controller 10 is a low-level signal. When the controller 10 outputs the first turn-off signal, the first capacitor C1 discharges through the third resistor R3 until it discharges to a level less than the turn-on voltage of the switch Q3. The switch Q3 then turns off, thereby controlling the switch Q2 to turn off. The first diode D1 is used to prevent the first turn-on signal from flowing through the third resistor R3 to the first capacitor C1, achieving unidirectional charge / discharge isolation and preventing circuit interference. Simultaneously, the first turn-off signal discharges the second capacitor C2 through the fourth resistor R4 until it discharges to a level lower than the turn-on voltage of the switch Q4, causing the switch Q4 to turn off and subsequently control the switch Q1 to turn on. Since the resistance of the third resistor R3 is less than that of the fourth resistor R4, the turn-off time of the switch Q4 is longer than the turn-on time of the switch Q3. That is, after the controller 10 outputs the first turn-on signal, the interlock unit 24 first controls the switch Q2 to turn off, and then controls the switch Q1 to turn on. The second diode D2 is used to prevent the signal from the second capacitor from discharging through the second resistor, avoiding uncontrollable timing and logical confusion caused by multiple path discharges, ensuring accurate interlocking action. By setting interlock units 24 in each charge / discharge control module 20, each battery pack 211 has an independent interlocking mechanism, which can be extended in series without affecting each other, providing a safe and reliable interlocking control scheme for high-series-count battery systems.

[0044] Furthermore, the second interlock control subunit 242 also includes a comparator U1. The non-inverting input terminal of the comparator U1 is connected to the first terminal of the second capacitor C2, the inverting input terminal of the comparator U1 is used to input the first power supply signal, and the output terminal of the comparator U1 is connected to the control terminal of the switching transistor Q4. Specifically, the first power signal is represented by VCC1. VCC1 can be set according to the actual application. It can be set to the turn-on voltage of switch Q2, or it can be set to a value greater than the turn-on voltage of switch Q2. When the voltage of the second capacitor C2 is higher than the first power signal VCC1, comparator U1 outputs a high-level signal to control switch Q4 to turn on, thereby controlling switch Q1 to turn off. When the voltage of the second capacitor C2 is lower than the first power signal VCC1, comparator U1 outputs a low-level signal to control switch Q4 to turn off, thereby controlling switch Q1 to turn on. By setting comparator U1, a voltage threshold judgment mechanism is added, triggering the interlock action only when the capacitor voltage is lower than the set threshold. This avoids malfunctions or timing chaos caused by slow capacitor discharge, improving the accuracy and stability of interlock control. Simultaneously, adjustable interlock time differences can be achieved by setting the parameters of each capacitor, resistor, and the first power signal, improving system adaptability.

[0045] In one embodiment, based on the above embodiments, such as Figure 5 As shown, the current sampling unit 23 includes a sampling resistor Rs, a third voltage divider unit 231, a fourth voltage divider unit 232, and an operational amplifier U2. One end of the sampling resistor Rs is connected to the first terminal of the switching transistor Q2, and the other end of the sampling resistor Rs serves as one end of the charge / discharge control module 20. One end of the third voltage divider unit 231 is connected to one end of the sampling resistor Rs, and the voltage divider node of the third voltage divider unit 231 is connected to the non-inverting input terminal of the operational amplifier U2. The other end of the third voltage divider unit 231 is used to input a second power supply signal, which is represented by VCC2. Specifically, the third voltage divider unit 231 includes a fifth voltage divider resistor Res5 and a sixth voltage divider resistor Res6.

[0046] One end of the fourth voltage divider unit 232 is connected to the other end of the sampling resistor Rs. The voltage divider node of the fourth voltage divider unit 232 is connected to the inverting input terminal of the operational amplifier U2. The other end of the fourth voltage divider unit 232 is connected to the output terminal of the operational amplifier U2. The fourth voltage divider unit 232 includes a seventh voltage divider resistor Res7 and an eighth voltage divider resistor Res8. The output terminal of the operational amplifier U2 is electrically connected to the controller 10. The power supply terminal of the operational amplifier U2 is used to input the third power supply signal. The second power supply signal VCC2 and the third power supply signal can be set according to the actual application. For example, the second power supply signal VCC2 is less than the third power supply signal to ensure that the controller 10 can obtain the positive current as the charging current and the negative current as the discharging current. It is understood that, using the current sampling unit 23 of this embodiment, each charge and discharge control module 20 should be connected in series with the corresponding bypass control switch 221 and the corresponding current sampling unit 23 in sequence.

[0047] This application also provides a power supply device, exemplary of which includes multiple battery packs and the aforementioned battery control circuit, wherein each battery pack is connected to a corresponding charge / discharge control module, and exemplary of which the power supply device is a lithium battery.

[0048] This application also provides an electric vehicle, exemplary of which includes the aforementioned power supply device. Exemplarily, the electric vehicle is a two-wheeled or three-wheeled vehicle, and uses a lithium battery to charge the two-wheeled or three-wheeled vehicle. This avoids the problems of short driving range and short cycle life that occur when electric two-wheeled or three-wheeled vehicles use lead-acid batteries. Furthermore, the lithium battery of this application can control the discharge control switch 212 corresponding to the current battery pack 211 to turn off and the bypass control switch 221 corresponding to the current battery pack 211 to turn on when the battery pack 211 is in a fully charged state or a low-charge state, so that the system as a whole can still operate normally, thereby improving the system's adaptability.

[0049] In the several embodiments provided in this application, it should be understood that the disclosed apparatus and methods can also be implemented in other ways. The apparatus embodiments described above are merely illustrative. For example, the flowcharts and block diagrams in the accompanying drawings show the architecture, functionality, and operation of possible implementations of apparatus, methods, and computer program products according to various embodiments of this application. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of code containing one or more executable instructions for implementing a specified logical function. It should also be noted that, in alternative implementations, the functions marked in the blocks may occur in a different order than those marked in the drawings. For example, two consecutive blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in the block diagram and / or flowchart, and combinations of blocks in the block diagram and / or flowchart, can be implemented using a dedicated hardware-based system that performs the specified function or action, or using a combination of dedicated hardware and computer instructions.

[0050] In addition, the functional modules or units in the various embodiments of this application can be integrated together to form an independent part, or each module can exist independently, or two or more modules can be integrated to form an independent part.

[0051] If the aforementioned functions are implemented as software functional modules and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a smartphone, personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application.

[0052] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application.

Claims

1. A battery control circuit, characterized in that, The control circuit includes: a controller and at least two charge / discharge control modules; each charge / discharge control module is used to connect to a corresponding battery pack. Each of the charging and discharging control modules includes: a discharge control switch, a bypass control switch, and a current sampling unit. The positive terminal of the battery pack, the bypass control switch, the discharge control switch, and the negative terminal of the battery pack are connected in sequence. The current sampling unit is connected to the battery pack and is used to acquire the charging and discharging current signal of the battery pack. The bypass control switches in each of the charging and discharging control modules are connected in series. The controller is electrically connected to the control terminal of each current sampling unit, each discharge control switch and each bypass control switch, respectively. The controller is used to determine the charging and discharging state of the battery pack based on the charging and discharging current signal. When the battery pack is fully charged, the bypass control switch is turned on; when the battery pack is discharged to a low charge level, the discharge control switch is turned off and the bypass control switch is turned on.

2. The battery control circuit according to claim 1, characterized in that, The charging and discharging control module also includes an interlocking unit. The input terminal of the interlocking unit is electrically connected to the controller, the first output terminal of the interlocking unit is connected to the control terminal of the bypass control switch, and the second output terminal of the interlocking unit is connected to the control terminal of the discharge control switch. In response to the first conduction signal of the controller, the interlock unit controls the discharge control switch to turn off and then controls the bypass control switch to turn on. In response to the first shutdown signal from the controller, the interlock unit controls the bypass control switch to turn off and then controls the discharge control switch to turn on.

3. The battery control circuit according to claim 2, characterized in that, The interlocking unit includes: a first interlocking switch, a second interlocking switch, a first interlocking control subunit, a second interlocking control subunit, a first pressure dividing subunit, and a second pressure dividing subunit; The first interlock control subunit is connected between the controller and the control terminal of the first interlock switch. The first terminal of the first interlock switch is connected to the other terminal of the first voltage divider subunit, and the second terminal of the first interlock switch is grounded. One terminal of the first voltage divider subunit is connected to the positive terminal of the battery pack, and the voltage divider node of the first voltage divider subunit is connected to the control terminal of the bypass control switch. The second interlock control subunit is connected between the controller and the control terminal of the second interlock switch. The first terminal of the second interlock switch is connected to the series node of the second voltage divider subunit, and the second terminal of the second interlock switch is grounded. One end of the second voltage divider subunit is electrically connected to the controller, and the other end of the second voltage divider subunit is connected to the negative terminal of the battery pack. The voltage divider node of the second voltage divider subunit is connected to the control terminal of the discharge control switch.

4. The battery control circuit according to claim 3, characterized in that, The first interlock control subunit includes a first resistor and a first capacitor. One end of the first resistor is electrically connected to the controller, and the other end of the first resistor is connected to the first terminal of the first capacitor. The first terminal of the first capacitor is connected to the control terminal of the first interlock switch, and the second terminal of the first capacitor is connected to the second terminal of the first interlock switch. The second interlock control subunit includes a second resistor and a second capacitor. One end of the second resistor is electrically connected to the controller, and the other end of the second resistor is connected to the first end of the second capacitor. The first end of the second capacitor is electrically connected to the control terminal of the second interlock switch, and the second end of the second capacitor is connected to the second terminal of the second interlock switch. The resistance value of the second resistor is less than the resistance value of the first resistor.

5. The battery control circuit according to claim 4, characterized in that, The first interlock control subunit further includes a first diode and a third resistor. One end of the third resistor is connected to the first terminal of the first capacitor, and the other end of the third resistor is connected to the positive terminal of the first diode. The negative terminal of the first diode is electrically connected to the controller. The second interlock control subunit further includes a second diode and a fourth resistor. The positive terminal of the second diode is electrically connected to the controller, and the negative terminal of the second diode is connected to one end of the second resistor. One end of the fourth resistor is connected to the first terminal of the second capacitor, and the other end of the fourth resistor is electrically connected to the controller. The resistance value of the third resistor is less than that of the fourth resistor.

6. The battery control circuit according to claim 4, characterized in that, The second interlock control subunit also includes a comparator. The non-inverting input of the comparator is connected to the first terminal of the second capacitor, the inverting input of the comparator is used to input a first power supply signal, and the output of the comparator is connected to the control terminal of the second interlock switch.

7. The battery control circuit according to claim 1, characterized in that, The current sampling unit includes a sampling resistor, a third voltage divider unit, a fourth voltage divider unit, and an operational amplifier. One end of the sampling resistor is connected to the first terminal of the bypass control switch, and the other end of the sampling resistor serves as one end of the charge / discharge control module. One end of the third voltage divider unit is connected to one end of the sampling resistor, and the voltage divider node of the third voltage divider unit is connected to the non-inverting input terminal of the operational amplifier. The other end of the third voltage divider unit is used to input a second power supply signal. One end of the fourth voltage divider unit is connected to the other end of the sampling resistor. The voltage divider node of the fourth voltage divider unit is connected to the inverting input terminal of the operational amplifier. The other end of the fourth voltage divider unit is connected to the output terminal of the operational amplifier. The output terminal of the operational amplifier is electrically connected to the controller. The power supply terminal of the operational amplifier is used to input a third power supply signal, and the second power supply signal is smaller than the third power supply signal.

8. The battery control circuit according to claim 1, characterized in that, The bypass control switch includes a switching transistor, the first end of which is connected to the positive terminal of the battery pack, the second end of which is connected to the first terminal of the discharge control switch, and the control terminal of the switching transistor is electrically connected to the controller.

9. A power supply device, characterized in that, The power supply device includes multiple battery packs and a battery control circuit according to any one of claims 1-8, wherein each battery pack is connected to a corresponding charge / discharge control module.

10. An electric vehicle, characterized in that, The electric vehicle includes the power supply device as described in claim 9.

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