Charging and discharging control circuit and electric device

Abstract

The application relates to a charging and discharging control circuit and a power consumption device. The charging and discharging control circuit comprises a charging control module connected with a backup battery; a switching switch module connected with the charging control module and a main battery for powering a load, the switching switch module being used in a first state or a second state, wherein the first state is a charging loop for connecting the charging control module and the main battery to connect the backup battery to power the main battery, and the second state is a discharging loop for connecting the main battery and the load; and a discharging control module connected with the main battery and the switching switch module. The application can automatically switch to the backup battery to charge the main battery, thereby solving the problem of insufficient battery power.

Description

Technical Field

[0001] This application relates to the field of charging and discharging technology, and in particular to a charging and discharging control circuit and an electrical device. Background Technology

[0002] With the development of new energy technologies, batteries are being used in a wider range of fields, such as new energy vehicles powered by batteries, intelligent robots, and drones.

[0003] Currently, due to limitations in battery capacity, electrical devices are prone to insufficient battery power, which seriously affects the user experience. Summary of the Invention

[0004] Therefore, it is necessary to provide a charging and discharging control circuit and an electrical device that can automatically switch to a backup battery to charge the main battery when the device's battery power is insufficient, thus solving the problem of insufficient battery power.

[0005] In a first aspect, this application provides a charge / discharge control circuit, comprising:

[0006] A charging control module is used to connect to a backup battery;

[0007] A switching module is used to connect the charging control module and the main battery that supplies power to the load. The switching module is used to be in a first state or a second state. The first state is used to connect the charging control module and the main battery to connect the backup battery to the main battery to supply power to the charging circuit. The second state is used to connect the main battery and the load to the discharging circuit.

[0008] The discharge control module connects the main battery and the switching module.

[0009] The charging control module is used to disconnect the connection with the switching module to break the charging circuit when the main battery is charged to the first preset voltage. The switching module is used to activate the discharge control module when a discharge signal is received. The activated discharge control module is used to control the switching module to switch from the first state to the second state. The activated discharge control module is also used to detect the voltage of the main battery during the discharge process of the main battery, and to maintain the second state of the switching module when the voltage of the main battery is greater than the second preset voltage, and to control the switching module to switch from the second state to the first state when the voltage of the main battery is less than the second preset voltage.

[0010] In one embodiment, the charge / discharge control circuit further includes a first voltage divider module for connecting to a backup battery and a second voltage divider module for connecting to a main battery;

[0011] The charging control module includes a comparison module and a switching module. The control terminal, the first voltage divider module, and the second voltage divider module of the switching module are respectively used to connect to the output terminal, the first input terminal, and the second input terminal of the comparison module. The output terminal of the switching module is used to connect to the backup battery and the switching module.

[0012] The first voltage divider module is used to acquire the first voltage divider signal, the second voltage divider module is used to acquire the second voltage divider signal, and the comparison module is used to output a connection signal and a disconnect signal to the control terminal of the switch module based on the result of comparing the first voltage divider signal and the second voltage divider signal. The connection signal is used to control the switch module to connect so as to conduct the switch module and the switching switch module to conduct the charging circuit of the backup battery and the main battery. The disconnect signal is used to control the switch module to disconnect so as to cut off the switch module and the switching switch module to disconnect the charging circuit of the backup battery and the main battery.

[0013] In one embodiment, the comparison module includes a comparator U2A, a resistor R9, a resistor R12, a resistor R13, and a diode D3;

[0014] The non-inverting input of comparator U2A is connected to the first voltage divider module and the first terminal of resistor R9, respectively. The inverting input of comparator U2A is connected to the second voltage divider module. The second terminal of resistor R9 is connected to the anode of diode D3, and the cathode of diode D3 is connected to the output terminal of comparator U2A. The first terminal of resistor R13 is connected to the output terminal of comparator U2A, and the second terminal of resistor R13 is connected to the control terminal of the switching module. The first terminal of resistor R13 is also connected to the power supply voltage through resistor R12.

[0015] In one embodiment, the switching module includes a switching transistor Q1, a transistor Q2, a resistor R3, a resistor R6, and a light-emitting diode LED1;

[0016] The control terminal of the switching transistor Q1 is connected to the first terminal of resistor R3 and the first terminal of resistor R6. The first terminal of the switching transistor Q1 is connected to the second terminal of resistor R3 and the backup battery. The second terminal of the switching transistor Q1 is connected to the switching module.

[0017] The base of transistor Q2 is connected to the output of the comparator module, the emitter of transistor Q2 is grounded, and the collector of transistor Q2 is connected to the cathode of light-emitting diode LED1.

[0018] The second end of resistor R6 is connected to the anode of LED1.

[0019] In one embodiment, the discharge control module includes a power detection module and a discharge self-locking module. The power detection module is connected to the main battery and is used to detect the power of the main battery during the discharge process. The discharge self-locking module is connected to the power detection module and the switching module.

[0020] When the power detection module detects that the voltage of the main battery is greater than the second preset voltage and the switching module receives a discharge signal, it sends a start signal to the discharge self-locking module. The started discharge self-locking module is used to control the switching module to switch from the first state to the second state.

[0021] When the power detection module detects that the voltage of the main battery is greater than the second preset voltage, the power detection module outputs a sustaining signal to the discharge self-locking module. The discharge self-locking module is used to maintain the second state of the switching module. When the power detection module detects that the voltage of the main battery is less than the second preset voltage, the power detection module outputs a switching signal to the discharge self-locking module. The discharge self-locking module is used to control the switching module to switch from the second state to the first state.

[0022] In one embodiment, the charge / discharge control circuit further includes a first voltage divider module and a third voltage divider module; the power detection module includes a comparator U2B.

[0023] The output, non-inverting input, and inverting input of comparator U2B are respectively connected to the discharge self-locking module, the first voltage divider module, and the third voltage divider module; the first voltage divider module is used to connect to the backup battery and obtain the third voltage divider signal, and the third voltage divider module is used to connect to the main battery and obtain the fourth voltage divider signal;

[0024] Comparator U2B is used to output a switching signal to the discharge self-locking module when the third voltage divider signal is greater than the fourth voltage divider signal; comparator U2B is used to output a sustaining signal to the discharge self-locking module when the third voltage divider signal is less than the fourth voltage divider signal.

[0025] In one embodiment, the discharge self-locking module includes a first control module, a second control module, and a third control module;

[0026] The control terminal of the first control module is connected to the discharge signal receiving port of the switching module. The first terminal of the first control module is connected to the control terminal of the second control module, and the second terminal of the first control module is grounded. The first terminal of the second control module is connected to the power supply voltage. The control terminal of the third control module is connected to the switching module and the second terminal of the second control module. The first terminal of the third control module is connected to the state switching port of the switching module, and the second terminal of the third control module is grounded.

[0027] When the power detection module detects that the voltage of the main battery is greater than the second preset voltage, the power detection module outputs a start signal to the control terminal of the second control module to start the discharge self-locking module.

[0028] When the discharge self-locking module is started and the switching module receives the discharge signal, the discharge signal is used to control the first control module to turn on. The turned-on first control module is used to control the second and third control modules to turn on. The turned-on third control module is used to output a low-level signal to the state switching port of the switching module, thereby controlling the switching module to switch to the second state.

[0029] During the discharge process of the main battery, when the power detection module detects that the voltage of the main battery is greater than the second preset voltage, the power detection module outputs a sustaining signal to the second control module. The first control module and the second control module maintain each other's conduction to maintain the conduction of the third control module, thereby controlling the third control module to continuously output a low-level signal to the state switching port of the switching module.

[0030] During the discharge process of the main battery, when the power detection module detects that the voltage of the main battery is less than the second preset voltage, the power detection module outputs a switching signal to the control terminal of the second control module. The switching signal is used to control the second control module and the third control module to disconnect, and the switching module returns from the second state to the first state.

[0031] In one embodiment, the first control module includes a transistor Q4 and a resistor R24;

[0032] The base of transistor Q4 is connected to the first terminal of resistor R24, the third control module, and the switching module, respectively. The emitter of transistor Q4 is grounded, and the collector of transistor Q4 is connected to the second control module.

[0033] The second terminal of resistor R24 ​​is grounded.

[0034] In one embodiment, the second control module includes a transistor Q3, a resistor R20, a resistor R21, and a capacitor C1;

[0035] The base of transistor Q3 is connected to the first end of resistor R20 and the first end of resistor R21, the emitter of transistor Q3 is connected to the power supply voltage, and the collector of transistor Q3 is connected to the third control module.

[0036] The second terminal of resistor R20 is connected to the power supply voltage;

[0037] The second terminal of resistor R21 is connected to the first control module;

[0038] The first terminal of capacitor C1 is connected to the power supply voltage, and the second terminal of capacitor C1 is connected to the first control module.

[0039] In one embodiment, the second control module includes transistor Q5, resistor R22, resistor R23, and diode D6;

[0040] The base of transistor Q5 is connected to the first end of resistor R22, the emitter of transistor Q5 is grounded, and the collector of transistor Q5 is connected to the switching module.

[0041] The second end of resistor R22 is connected to the first end of resistor R23 and the cathode of diode D6, respectively. The second end of resistor R23 is connected to the switching module.

[0042] The anode of diode D6 is grounded.

[0043] In one embodiment, the switching module includes a switching switch RLY1, a discharge button SW1, and a diode D4;

[0044] The first end of the discharge button SW1 is connected to the first end of the main battery, and the second end of the discharge button SW1 is connected to the second end of the main battery through diode D4.

[0045] The switch RLY1 is used to connect the first terminal of the main battery, the discharge control module, the charging control module, and the load terminal;

[0046] The discharge button SW1 is used to provide the operating voltage to the discharge control module to start the discharge control module after receiving a discharge signal;

[0047] The discharge control module is used to control the switching switch RLY1 to connect the main battery and the load terminal. When the voltage of the main battery is greater than the second preset voltage, the discharge control module is used to maintain the switching switch RLY1 in the state of connecting the main battery and the load terminal. When the voltage of the main battery is less than the second preset voltage, the discharge control module is used to control the switching switch RLY1 to switch from the state of connecting the main battery and the load terminal to the state of connecting the main battery and the charging control module.

[0048] In one embodiment, the charge / discharge control circuit further includes a first voltage divider module, a second voltage divider module, and an automatic switch drive module, wherein the automatic switch drive module is connected to the first voltage divider module, the second voltage divider module, and the discharge control module;

[0049] The first voltage divider module is used to connect to the backup battery and acquire the first voltage divider signal, the second voltage divider module is used to connect to the main battery and acquire the second voltage divider signal, and the automatic switch drive module is used to automatically control the discharge control module to achieve automatic switching between the first state and the second state based on the comparison result of the first voltage divider signal and the second voltage divider signal.

[0050] Secondly, this application provides an electrical device that includes a main battery, a backup battery, and a charge / discharge control circuit as described in any one of the first aspects.

[0051] In the aforementioned charging and discharging control circuit and electrical equipment, the charging and discharging control circuit includes: a charging control module for connecting a backup battery; a switching module for connecting the charging control module and a main battery that supplies power to the load, the switching module being in a first state or a second state, wherein the first state is a charging circuit for connecting the charging control module and the main battery to supply power to the main battery via the backup battery, and the second state is a discharging circuit for connecting the main battery and the load; a discharging control module is connected to the main battery and the switching module; the charging control module is used to cut off the charging circuit when the main battery is charged to a first preset voltage; the switching module is used to activate the discharging control module when a discharging signal is received, the activated discharging control module is used to control the switching module to switch from the first state to the second state; the activated discharging control module is also used to detect the voltage of the main battery during the main battery discharge process, and is used to maintain the second state of the switching module when the voltage of the main battery is greater than the second preset voltage, and is also used to control the switching module to switch from the second state to the first state when the voltage of the main battery is less than the second preset voltage. This embodiment of the application, through the cooperation between the charging control module, the switching module, and the discharging control module, can automatically switch to the backup battery to charge the main battery when the main battery is low in power. After the main battery is fully charged, the main battery will then supply power to the load, thus solving the problem of insufficient battery power. Attached Figure Description

[0052] To more clearly illustrate the technical solutions in the embodiments of this application or the conventional technology, the drawings used in the description of the embodiments or the conventional technology will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0053] Figure 1 This is one of the schematic diagrams of the charge / discharge control circuit in one embodiment;

[0054] Figure 2 This is a second schematic diagram of the charge / discharge control circuit in one embodiment;

[0055] Figure 3 This is the third schematic diagram of the charging and discharging control circuit in one embodiment;

[0056] Figure 4 This is a fourth schematic diagram of the charge / discharge control circuit in one embodiment;

[0057] Figure 5 This is the fifth schematic diagram of the charging and discharging control circuit in one embodiment;

[0058] Figure 6This is a schematic diagram of the charging and discharging control circuit in one embodiment;

[0059] Figure 7 This is the seventh schematic diagram of the charging and discharging control circuit in one embodiment;

[0060] Figure 8 This is the eighth schematic diagram of the charging and discharging control circuit in one embodiment;

[0061] Figure 9 This is the ninth schematic diagram of the charging and discharging control circuit in one embodiment.

[0062] Explanation of reference numerals in the attached figures:

[0063] BAT1, Backup Battery; BAT2, Main Battery; 11, Charging Control Module; 12, Switching Switch Module;

[0064] 13. Discharge control module; 14. First voltage divider module; 15. Second voltage divider module;

[0065] 16. Third voltage divider module; 17. Automatic switch drive module; 18. Auxiliary power supply circuit;

[0066] 111. Comparison module; 112. Switch module; 131. Power detection module; 132. Discharge self-locking module;

[0067] U2A, comparator; U2B, comparator; U3C, comparator;

[0068] R1, resistor; R2, resistor; R3, resistor; R5, resistor; R6, resistor; R7, resistor;

[0069] R8, resistor; R9, resistor; R10, resistor; R11, resistor; R12, resistor; R13, resistor;

[0070] R14, resistor; R16, resistor; R17, resistor; R18, resistor; R20, resistor;

[0071] R21, resistor; R22, resistor; R23, resistor; R24, resistor;

[0072] Q1, Switching transistor; Q2, Transistor; Q3, Transistor; Q4, Transistor; Q5, Transistor;

[0073] LED1, Light Emitting Diode; LED2, Light Emitting Diode; Adj, Voltage Processing Chip;

[0074] D1, diode; D2, diode; D3, diode; D4, diode; D5, diode;

[0075] D6, diode; D7, diode; C1, capacitor; EC1, capacitor; EC2, capacitor. Detailed Implementation

[0076] To facilitate understanding of this application, a more complete description will be provided below with reference to the accompanying drawings, which illustrate embodiments of the present application. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that the disclosure of this application will be thorough and complete.

[0077] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.

[0078] It is understood that the terms "first," "second," etc., used herein may be used to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish one element from another. For example, without departing from the scope of this application, a first resistor may be referred to as a second resistor, and similarly, a second resistor may be referred to as a first resistor. Both the first resistor and the second resistor are resistors, but they are not the same resistor.

[0079] It is understood that the term "connection" in the following embodiments should be understood as "electrical connection," "communication connection," etc., if the connected circuits, modules, units, etc., have electrical signal or data transmission with each other.

[0080] It is understandable that "at least one" refers to one or more, and "multiple" refers to two or more. "At least a part of an element" refers to part or all of an element.

[0081] When used herein, the singular forms of “a,” “an,” and “the” may also include the plural forms unless the context clearly indicates otherwise. It should also be understood that the terms “comprising / including” or “having,” etc., specify the presence of the stated features, wholes, steps, operations, components, parts, or combinations thereof, but do not preclude the possibility of the presence or addition of one or more other features, wholes, steps, operations, components, parts, or combinations thereof. Meanwhile, the term “and / or” as used in this specification includes any and all combinations of the associated listed items.

[0082] With the development of new energy technologies, batteries are being used in an increasingly wide range of fields, such as battery-powered new energy vehicles, intelligent robots, and drones. Currently, however, electrical devices are often limited by battery capacity, leading to insufficient battery power and severely impacting user experience.

[0083] To address the aforementioned issues, this application provides a charging and discharging control circuit that can automatically switch to a backup battery to charge the main battery when the device's battery power is insufficient, thus solving the problem of insufficient battery power.

[0084] In one exemplary embodiment, such as Figure 1 As shown, a charge / discharge control circuit is provided, comprising a charging control module 11, a switching module 12, and a discharging control module 13. The charging control module 11 is used to connect a backup battery BAT1. The switching module 12 is used to connect the charging control module 11 and a main battery BAT2 that supplies power to the load. The switching module 12 is configured to be in either a first state or a second state; wherein, the first state is a charging circuit connecting the charging control module 11 and the main battery BAT2 to supply power from the backup battery BAT1 to the main battery BAT2; and the second state is a discharging circuit connecting the main battery BAT2 and the load. The discharging control module 13 is connected to the main battery BAT2 and the switching module 12.

[0085] The charging control module 11 disconnects the charging circuit by cutting off the connection with the switching module 12 when the main battery BAT2 is charged to a first preset voltage. The switching module 12 activates the discharge control module 13 upon receiving a discharge signal. The activated discharge control module 13 controls the switching module 12 to switch from a first state to a second state. The activated discharge control module 13 also detects the voltage of the main battery BAT2 during discharge and maintains the switching module 12 in the second state when the voltage of the main battery BAT2 is greater than a second preset voltage, and controls the switching module 12 to switch from the second state to the first state when the voltage of the main battery BAT2 is less than the second preset voltage. The first preset voltage value is greater than the second preset voltage value.

[0086] When the main battery BAT2 has insufficient power, i.e., when the voltage of the main battery BAT2 is lower than the second preset voltage, the switching module 12 is in the first state, connecting the charging control module 11 and the main battery BAT2, so that the backup battery BAT1 is connected to the main battery BAT2 through the charging control module 11 to charge the main battery BAT2. When the main battery BAT2 is charged to the first preset voltage, the charging control module 11 cuts off the charging circuit, and the backup battery BAT1 stops charging the main battery BAT2.

[0087] When the switching module 12 receives a discharge signal, it activates the discharge control module 13. The activated discharge control module 13 controls the switching module 12 to switch from a first state to a second state, that is, from the charging circuit connecting the backup battery BAT1 and the main battery BAT2 to the discharge circuit connecting the main battery BAT2 and the load, so that the main battery BAT2 supplies power to the load. The discharge signal can be received through devices such as buttons or switches; that is, when the user triggers a button or switch, the switching module 12 receives the discharge signal.

[0088] During the discharge process of the main battery BAT2, the activated discharge control module 13 detects the voltage of the main battery BAT2. When the voltage of the main battery BAT2 is greater than the second preset voltage, that is, when the main battery BAT2 has sufficient charge, the activated discharge control module 13 maintains the second state of the switching module 12, that is, maintains the state in which the switching module 12 connects the discharge circuit between the main battery BAT2 and the load, so that the main battery BAT2 can continuously discharge to the load.

[0089] When the voltage of the main battery BAT2 is less than the second preset voltage, that is, when the main battery BAT2 is low on power, the discharge control module 13 controls the switching switch module 12 to switch from the second state to the first state, that is, to switch from the discharge circuit connecting the main battery BAT2 and the load to the charging circuit connecting the backup battery BAT1 and the main battery BAT2, so that the backup battery BAT1 charges the main battery BAT2.

[0090] In the above embodiments, the charging and discharging control circuit includes a charging control module, a switching module, and a discharging control module. The charging control module, the switching module, and the discharging control module cooperate with each other to automatically switch to the backup battery to charge the main battery when the main battery is low on power. After the main battery is fully charged, the main battery then supplies power to the load, thus solving the problem of insufficient battery power.

[0091] In one exemplary embodiment, such as Figure 2 As shown, the charge / discharge control circuit also includes a first voltage divider module 14 for connecting the backup battery BAT1 and a second voltage divider module 15 for connecting the main battery BAT2. The charging control module 11 includes a comparator module 111 and a switch module 112.

[0092] Specifically, the control terminal of the switch module 112, the first voltage divider module 14, and the second voltage divider module 15 are respectively connected to the output terminal, the first input terminal, and the second input terminal of the comparison module 111. The output terminal of the switch module 112 is connected to the backup battery BAT1 and the switching module 12. The first voltage divider module 14 is used to acquire the first voltage divider signal, and the second voltage divider module 15 is used to acquire the second voltage divider signal. The comparison module 111 is used to output a connection signal and a disconnect signal to the control terminal of the switch module based on the result of comparing the first voltage divider signal and the second voltage divider signal. The connection signal is used to control the switch module to connect to conduct the switch module and the switching module, thereby conducting the charging circuit of the backup battery and the main battery. The disconnect signal is used to control the switch module to disconnect the switch module and the switching module, thereby disconnecting the charging circuit of the backup battery and the main battery.

[0093] In this embodiment, the first voltage divider module 14 inputs the first voltage divider signal to the first input terminal of the comparison module 111, and the second voltage divider module 15 inputs the second voltage divider signal to the second input terminal of the comparison module 111. The comparison module 111 compares the first voltage divider signal and the second voltage divider signal. If the first voltage divider signal is greater than the second voltage divider signal, the comparison module 111 outputs a connection signal to the control terminal of the switch module 112. The switch module 112 remains in a conducting state according to the connection signal, thereby realizing the connection of the charging circuit between the backup battery BAT1 and the main battery BAT2. That is, the backup battery BAT1 can be connected to the main battery BAT2 through the connected switch module 112 and the switching module 12 to charge the main battery BAT2. If the first voltage divider signal is less than the second voltage divider signal, the comparison module 111 outputs a disconnect signal to the control terminal of the switch module 112. The switch module 112 is in the disconnected state according to the disconnect signal, thereby disconnecting the charging circuit between the backup battery BAT1 and the main battery BAT2. That is, after the switch module 112 is disconnected, the switch module 112 and the switching module 12 are in the disconnected state, thereby disconnecting the connection between the backup battery BAT1 and the main battery BAT2, stopping the charging of the main battery BAT2, thus avoiding overcharging of the main battery BAT2.

[0094] In the above embodiments, the present application uses a first voltage divider module and a second voltage divider module to sample the voltage of the backup battery and the main battery. In conjunction with a comparison module and a switching module, the backup battery can charge the main battery or disconnect the charging circuit. In solving the problem of insufficient battery power, the battery can also be effectively protected and its lifespan extended.

[0095] In one exemplary embodiment, such as Figure 3As shown, the comparison module 111 includes a comparator U2A, resistors R9, R12, and R13, and a diode D3. The non-inverting input of comparator U2A is connected to the first voltage divider module and the first terminal of resistor R9, respectively. The inverting input of comparator U2A is connected to the second voltage divider module. The second terminal of resistor R9 is connected to the anode of diode D3, and the cathode of diode D3 is connected to the output terminal of comparator U2A. The first terminal of resistor R13 is connected to the output terminal of comparator U2A, and the second terminal of resistor R13 is connected to the control terminal of the switching module. The first terminal of resistor R13 is also connected to the power supply voltage VCC through resistor R12.

[0096] The first voltage divider module 14 divides the voltage of the backup battery BAT1 to obtain a first voltage divider signal, and inputs the first voltage divider signal to the non-inverting input of comparator U2A. The second voltage divider module 15 divides the voltage of the main battery BAT2 to obtain a second voltage divider signal, and inputs the second voltage divider signal to the inverting input of comparator U2A. Comparator U2A compares the first voltage divider signal and the second voltage divider signal. If the first voltage divider signal is greater than the second voltage divider signal, comparator U2A outputs a connection signal to the control terminal of switch module 112 through resistor R13. Switch module 112 connects the backup battery BAT1 and the switching module 12 according to the connection signal, so that the backup battery BAT1 can be connected to the main battery BAT2 through the switching module 12 to charge the main battery BAT2. If the first voltage divider signal is less than the second voltage divider signal, the comparator U2A outputs a disconnect signal to the control terminal of the switch module 112 through the resistor R13. The switch module 112 disconnects the backup battery BAT1 and the switching module 12 according to the disconnect signal, so that the connection between the backup battery BAT1 and the main battery BAT2 is disconnected, and the backup battery BAT1 stops charging the main battery BAT2.

[0097] In this circuit, resistor R9 and diode D3 form a hysteresis circuit to prevent the switch module 112 from disconnecting the connection between the backup battery BAT1 and the main battery BAT2 when the main battery BAT2 is fully charged. The calculation of the hysteresis voltage can include: assuming the voltage drop across diode D3 is Vd (0.3), when fully charged, the output voltage of comparator UA is low, forming a loop from the power supply voltage VCC through resistor R11, resistor R9, diode D3 to ground GND. Let V1 refer to the voltage at the non-inverting input of comparator U2A without resistor R9 and diode D3, and V1' refer to the voltage at the non-inverting input with resistor R9 and diode D3. Here, V1 = (VCC - Vd) / (R11 + R9) * R9. By adjusting resistor R9 to make V1' less than V1, the reference voltage (non-inverting input voltage) is changed; for example, when fully charged from 13.6V, it can be reduced to 13V.

[0098] Resistor R13 can limit the output current of comparator U2A and protect switch module 112.

[0099] In the above embodiments, the comparison module includes comparator U2A, resistor R9, resistor R12, resistor R13 and diode D3; the comparison module is constructed using comparators, the circuit structure is simple and easy to implement, and it can operate stably.

[0100] In one exemplary embodiment, such as Figure 3 As shown, the switching module 112 includes a switching transistor Q1, a transistor Q2, a resistor R3, a resistor R6, and a light-emitting diode LED1.

[0101] In this embodiment, the control terminal of switch Q1 is connected to the first terminals of resistor R3 and resistor R6, the first terminal of switch Q1 is connected to the second terminal of resistor R3 and backup battery BAT1, and the second terminal of switch Q1 is connected to the switching module 12. In one specific embodiment, switch Q1 can be a MOSFET, and the control terminal, first terminal and second terminal of switch Q1 are the gate, source and drain of the MOSFET, respectively.

[0102] Specifically, the base of transistor Q2 is connected to the output terminal of comparator module 111, and the base of transistor Q2 is connected to the second terminal of resistor R13 in comparator module 111. The emitter of transistor Q2 is grounded, and the collector of transistor Q2 is connected to the cathode of light-emitting diode LED1. The second terminal of resistor R6 is connected to the anode of light-emitting diode LED1.

[0103] Resistor R3 limits the voltage between the control terminal and the first terminal of switch Q1, providing the turn-on voltage for switch Q1. Resistor R6 limits the input current to switch Q1, protecting switch Q1.

[0104] Understandably, when the first voltage divider signal fed back by the first voltage divider module 14 is greater than the second voltage divider signal fed back by the second voltage divider module 15, it indicates that the voltage of the main battery BAT2 during the charging process is less than the first preset voltage. This means that the main battery BAT2 needs to continue charging through the backup battery BAT1. The high-level connection signal output by the comparison module 111 is transmitted to the base of transistor Q2, causing transistor Q2 to conduct, which in turn illuminates the light-emitting diode LED1, and the switching transistor Q1 is turned on. When the switching transistor Q1 is on, it connects with the backup battery BAT1. The conducting switching transistor Q1 can provide a high-level signal to the switching module 12, thereby switching the conduction state of the switching module 12 and the main battery BAT2. Thus, the charging circuit between the backup battery BAT1 and the main battery BAT2 is connected, and the backup battery BAT1 charges the main battery BAT2. The illumination of the light-emitting diode LED1 indicates that the charging circuit between the backup battery BAT1 and the main battery BAT2 is connected.

[0105] Understandably, when the first voltage divider signal fed back by the first voltage divider module 14 is less than the second voltage divider signal fed back by the second voltage divider module 15 connected to the main battery BAT2, it indicates that the voltage of the main battery BAT2 during charging is greater than the first preset voltage. This indicates that the main battery BAT2 is fully charged, and to avoid overcharging, the charging circuit between the backup battery BAT1 and the main battery BAT2 needs to be disconnected. When the first voltage divider signal is less than the second voltage divider signal, the low-level disconnect signal output by the comparison module 111 is transmitted to the base of the transistor Q2, causing the transistor Q2 to turn off, thereby turning off the light-emitting diode LED1 and the switching transistor Q1. Due to the disconnection of the switching transistor Q1, the switching module 12 receives a low-level signal, causing the switching module 12 to disconnect from the main battery BAT2, thereby disconnecting the charging circuit between battery BAT1 and the main battery BAT2, and the backup battery BAT1 no longer charges the main battery BAT2. The turning off of the light-emitting diode LED1 indicates that the charging circuit between the backup battery BAT1 and the main battery BAT2 is disconnected.

[0106] In the above embodiments, a switching module is formed by switching transistor Q1 and transistor Q2, which can turn on or off the connection between the backup battery and the main battery, thereby controlling the on / off of the charging circuit between the backup battery and the main battery, and providing support for the backup battery to automatically charge the main battery.

[0107] In one exemplary embodiment, such as Figure 4 As shown, the discharge control module 13 includes a power detection module 131 and a discharge self-locking module 132. The power detection module 131 is connected to the main battery BAT2 and is used to detect the power level of the main battery BAT2 during discharge. The discharge self-locking module 132 is connected to the power detection module 131 and the switching module 12. When the power detection module 131 detects that the voltage of the main battery BAT2 is greater than a second preset voltage and the switching module 12 receives a discharge signal, it sends a start signal to the discharge self-locking module 132. The activated discharge self-locking module 132 is used to control the switching module 12 to switch from a first state to a second state. When the power detection module 131 detects that the voltage of the main battery BAT2 is greater than the second preset voltage, the power detection module 131 outputs a sustaining signal to the discharge self-locking module 132, which is used to maintain the second state of the switching module 12; when the power detection module 131 detects that the voltage of the main battery BAT2 is less than the second preset voltage, the power detection module 131 outputs a switching signal to the discharge self-locking module 132, which is used to control the switching module 12 to switch from the second state to the first state.

[0108] When the switching module 12 receives a discharge signal, it sends a start signal to the discharge self-locking module 132. The started discharge self-locking module 132 controls the switching module 12 to switch from the first state to the second state, that is, to switch from the charging circuit connecting the backup battery BAT1 and the main battery BAT2 to the discharge circuit connecting the main battery BAT2 and the load, so that the main battery BAT2 supplies power to the load.

[0109] During the discharge process of the main battery BAT2, the power detection module 131 can detect the voltage of the main battery BAT2. If the voltage of the main battery BAT2 is greater than the second preset voltage, it indicates that the main battery BAT2 has sufficient power. Then, the power detection module 131 outputs a maintenance signal to the discharge self-locking module 132. The discharge self-locking module 132 maintains the second state of the switching module 12 according to the maintenance signal, that is, maintains the state in which the switching module 12 connects the discharge circuit between the main battery BAT2 and the load. If the voltage of the main battery BAT2 is less than the second preset voltage, it indicates that the main battery BAT2 has insufficient power. Then, the power detection module 131 outputs a switching signal to the discharge self-locking module 132. The discharge self-locking module 132 controls the switching module 12 to switch from the second state to the first state according to the switching signal, that is, switch from the discharge circuit connecting the main battery BAT2 and the load to the charging circuit connecting the backup battery BAT1 and the main battery BAT2, so that the backup battery BAT1 charges the main battery BAT2. The power detection module 131 detects the power level of the main battery BAT2 during the discharge process and feeds back the detected power level to the discharge self-locking module 132. This causes the discharge self-locking module 132 to perform discharge self-locking to maintain the discharge process or abandon maintaining it, or to abandon maintaining the discharge process. This allows the main battery BAT2 to switch between the discharge and charging states, thereby enabling the main battery BAT2 to supply power to the load while preventing the main battery from being over-discharged, so as not to affect the battery's lifespan.

[0110] In one exemplary embodiment, such as Figure 5As shown, the charge / discharge control circuit also includes a first voltage divider module 14 and a third voltage divider module 16. The power detection module 131 includes a comparator U2B, whose output, non-inverting input, and inverting input are respectively connected to the discharge self-locking module 132, the first voltage divider module 14, and the third voltage divider module 16. The first voltage divider module 14 is also used to connect to the backup battery BAT1 and obtain the third voltage divider signal; that is, the first voltage divider module 14 can divide the voltage based on the backup battery BAT1 to obtain the third voltage divider signal. The third voltage divider module 16 is used to connect to the main battery BAT2 and obtain the fourth voltage divider signal; that is, the third voltage divider module 16 divides the voltage based on the main battery BAT2 to obtain the fourth voltage divider signal. The comparator U2B is used to output a switching signal to the discharge self-locking module 132 when the third voltage divider signal is greater than the fourth voltage divider signal; the comparator U2B is used to output a sustaining signal to the discharge self-locking module 132 when the third voltage divider signal is less than the fourth voltage divider signal.

[0111] The inverting input of comparator U2B is connected to the third voltage divider module 16 through resistor R19, and the output of comparator U2B is connected to the discharge self-locking module 132 through diode D5. Specifically, the anode of diode D5 is connected to the output of comparator U2B, and the cathode of diode D5 is connected to the discharge self-locking module 132.

[0112] It is worth noting that during the discharge process of the main battery BAT2, when the third voltage divider signal fed back from the first voltage divider module 14 to the non-inverting input of the comparator U2B is greater than the fourth voltage divider signal fed back from the third voltage divider module 16 to the inverting input of the comparator U2B, the comparator U2B outputs a high-level switching signal to the discharge self-locking module 132. The discharge self-locking module 132 controls the switching switch module 12 to switch from the second state to the first state according to the switching signal, that is, the discharge circuit between the main battery BAT2 and the load is disconnected. When the third voltage divider signal is greater than the fourth voltage divider signal, it indicates that the main battery BAT2 is low on charge. To prevent the main battery BAT2 from being over-discharged, the main battery BAT2 no longer supplies power to the load.

[0113] Similarly, if the third voltage divider signal is less than the fourth voltage divider signal, the comparator U2B outputs a low-level sustaining signal to the discharge self-locking module 132, and the discharge self-locking module 132 maintains the second state of the switching module 12, that is, keeps the discharge circuit of the main battery BAT2 supplying power to the load in the conducting state and continuously supplies power to the load.

[0114] Further combined with reference Figures 6 to 9 The first voltage divider module 14 includes resistors R11, R14, and R18 connected in series. The second voltage divider module 15 includes resistors R10 and R16 connected in series. The third voltage divider module 16 includes resistors R7 and R17 connected in series.

[0115] Specifically, the first terminal of resistor R11 is connected to the backup battery BAT1. The second terminal of resistor R11 is connected to the first terminal of resistor R14 and the non-inverting input of comparator U2A. The second terminal of resistor R14 is connected to the non-inverting input of comparator U2B and the first terminal of resistor R18. The second terminal of resistor R18 is grounded. The first terminal of resistor R10 is connected to the second terminal of switching transistor Q1. The second terminal of resistor R10 is connected to the first terminal of resistor R16 and the inverting input of comparator U2A. The second terminal of resistor R16 is grounded (GND). The first terminal of resistor R7 is connected to pin 4 of the toggle switch RLY1, the first terminal of resistor R8, and the first terminal of resistor RL. The second terminal of resistor R7 is connected to the cathode of diode D4, the first terminal of resistor R17, and the first terminal of resistor R19. The second terminal of resistor R17 is grounded.

[0116] In one exemplary embodiment, such as Figure 9 As shown, the charge / discharge control circuit also includes an auxiliary power supply circuit 18, which includes a diode D2, a voltage processing chip Adj, a capacitor EC1, and a capacitor EC2. The anode of diode D2 is connected to the backup battery BAT1, and the cathode of diode D2 is connected to the input terminal of the voltage processing chip Adj and the first terminal of capacitor EC1, respectively. The output terminal of the voltage processing chip Adj is connected to the first voltage divider module 14 and the first terminal of capacitor EC2, and the output terminal of the voltage processing chip Adj is the power supply voltage terminal. The second terminal of capacitor EC1 is grounded, and the second terminal of capacitor EC2 is grounded.

[0117] Among them, the voltage processing chip Adj is a three-terminal voltage regulator chip, which obtains the power supply voltage VCC based on the voltage of the backup battery BAT1 to ensure the stable operation of the charging and discharging control circuit. The first terminal of the resistor R11 of the first voltage divider module 14 is connected to the power supply voltage VCC, so the first voltage divider module 14 provides a first voltage divider signal based on the power supply voltage VCC to comparator U2A and a third voltage divider signal based on the power supply voltage VCC to comparator U2B.

[0118] In one exemplary embodiment, such as Figure 6 As shown, the switching module 12 includes a switching switch RLY1, a discharge button SW1, and a diode D4. The first terminal of the discharge button SW1 is connected to the first terminal of the main battery BAT2, and the second terminal of the discharge button SW1 is connected to the second terminal of the main battery BAT2 via the diode D4. The second terminal of the discharge button SW1 is connected to the anode of the diode D4, and the cathode of the diode D4 is connected to the second terminal of the main battery BAT2. The switching switch RLY1 is used to connect the first terminal of the main battery BAT2, the discharge control module 13, the charging control module 11, and the load terminal.

[0119] The discharge button SW1 is used to provide operating voltage to the discharge control module 13 upon receiving a discharge signal, thereby activating the discharge control module 13. Activating the discharge control module 13 controls the switch RLY1 to connect the main battery BAT2 and the load terminal. When the voltage of the main battery BAT2 is greater than a second preset voltage, the discharge control module 13 maintains the switch RLY1 in the state of connecting the main battery BAT2 and the load terminal; when the voltage of the main battery BAT2 is less than the second preset voltage, the discharge control module 13 controls the switch RLY1 to switch from the state of connecting the main battery BAT2 and the load terminal to the state of connecting the main battery BAT2 and the charging control module 11. The first terminal and the second terminal BAT2 of the main battery are the positive and negative terminals of the main battery BAT2, respectively; the second state is equivalent to the switch RLY1 being in the state of connecting the main battery BAT2 and the load terminal, and the first state is equivalent to the state of connecting the main battery BAT2 and the charging control module 11.

[0120] In one specific embodiment, the switch RLY1 is a relay, and the discharge button SW1 is a push-button switch. The second terminal of the discharge button SW1 is connected to the input terminal of the discharge self-locking module 132. The first input terminal of the coil of the switch RLY1 is connected to the power supply voltage VCC, and the second input terminal of the coil of the switch RLY1 is connected to the output terminal of the discharge self-locking module 132, which is the collector of the transistor Q5. The common terminal COM of the switch RLY1 is connected to the first terminal of the main battery BAT2, the normally open terminal NO of the switch RLY1 is connected to the drain of the switching transistor Q1, and the normally closed terminal NC of the switch RLY1 is connected to the load terminal. The first input terminal, the second input terminal, the common terminal COM, the normally open terminal NO, and the normally closed terminal NC are pins 1, 2, 3, 4, and 5 of the switch RLY1, respectively.

[0121] In the above embodiments, the switching module includes a switching switch RLY1, a discharge button SW1, and a diode D4. This embodiment obtains a discharge signal through the discharge button SW1 and uses the switching switch RLY1 to achieve automatic state switching, ensuring smooth switching between the backup battery charging the main battery and the main battery supplying power to the load.

[0122] In one exemplary embodiment, such as Figure 5 As shown, the discharge self-locking module 132 includes a first control module 1321, a second control module 1322 and a third control module 1323.

[0123] The control terminal of the first control module 1321 is connected to the discharge signal receiving port VBAT2 of the switching module 12. The first terminal of the first control module 1321 is connected to the control terminal of the second control module 1322, and the second terminal of the first control module 1321 is grounded to GND. The first terminal of the second control module 1322 is connected to the power supply voltage VCC. The control terminal of the third control module 1323 is connected to the second terminal of the switching module 12 and the second control module 1322. The first terminal of the third control module 1323 is connected to the state switching port D_RLY of the switching module 12, and the second terminal of the third control module 1323 is grounded to GND.

[0124] When the power detection module 131 detects that the voltage of the main battery BAT2 is greater than the second preset voltage, the power detection module 131 outputs a start signal to the control terminal of the second control module 1322 to start the discharge self-locking module 132. When the discharge self-locking module 132 is started and the switching module 12 receives a discharge signal, the discharge signal is used to control the first control module 1321 to be turned on. The turned-on first control module 1321 is used to control the second control module 1322 and the third control module 1323 to be turned on. The turned-on third control module 1323 is used to output a low-level signal to the state switching port D_RLY of the switching module 12, thereby controlling the switching module 12 to switch to the second state.

[0125] During the discharge process of the main battery BAT2, when the power detection module 131 detects that the voltage of the main battery BAT2 is greater than the second preset voltage, the power detection module 131 outputs a sustaining signal to the second control module 1322. The first control module 1321 and the second control module 1322 maintain mutual conduction to maintain the conduction of the third control module 1323, thereby controlling the third control module 1323 to continuously output a low-level signal to the state switching port D_RLY of the switching module 12. In one embodiment, the low-level signal is transmitted to pin 2 of the switching switch RLY1.

[0126] In one embodiment, the first control module 1321 includes a transistor Q4 and a resistor R24; the base of the transistor Q4 is connected to the first terminal of the resistor R24, the third control module 1323 and the switching module 12 respectively; the emitter of the transistor Q4 is grounded to GND; the collector of the transistor Q4 is connected to the second control module 1322; and the second terminal of the resistor R24 ​​is grounded to GND.

[0127] In one embodiment, the second control module 1322 includes a transistor Q3, a resistor R20, a resistor R21, and a capacitor C1; the base of transistor Q3 is connected to the first terminals of resistors R20 and R21, the emitter of transistor Q3 is connected to the power supply voltage VCC, and the collector of transistor Q3 is connected to the third control module 1323; the second terminal of resistor R20 is connected to the power supply voltage VCC; the second terminal of resistor R21 is connected to the first control module 1321; the first terminal of capacitor C1 is connected to the power supply voltage VCC, and the second terminal of capacitor C1 is connected to the first control module 1321.

[0128] In one embodiment, the second control module 1322 includes a transistor Q5, a resistor R22, a resistor R23, and a diode D6; the base of transistor Q5 is connected to the first end of resistor R22, the emitter of transistor Q5 is grounded to GND, and the collector of transistor Q5 is connected to the switching module 12; the second end of resistor R22 is connected to the first end of resistor R23 and the cathode of diode D6, and the second end of resistor R23 is connected to the switching module 12; the anode of diode D6 is grounded to GND.

[0129] Furthermore, the base of transistor Q4 is connected to the second terminal of discharge button SW1, the base of transistor Q3 is connected to the cathode of diode D5 through resistor R21, and the collector of transistor Q5 is connected to the second input terminal (pin 2) of the coil of switch RLY1.

[0130] In one specific embodiment, transistor Q3 is a PNP transistor, and transistors Q4 and Q5 are NPN transistors.

[0131] When comparator U2B determines that the third voltage divider signal is greater than the fourth voltage divider signal, it means that the main battery BAT2 has insufficient power, and the output of comparator U2B outputs a high level. This high level is transmitted to the base of transistor Q3 through diode D5, transistor Q3 is turned off, and the discharge self-locking module 132 does not work. Specifically, when the third voltage divider signal is greater than the fourth voltage divider signal, the output of comparator U2B outputs a high level through diode D5 to the base of transistor Q3 in the discharge self-locking module 132. Since the emitter of transistor Q3 is connected to the power supply voltage VCC, transistor Q3 is not conducting, and transistors Q4 and Q5 are also not conducting. At this time, it means that the discharge self-locking module 132 is not in the discharge self-locking state because the main battery BAT2 has insufficient power and cannot discharge, that is, there is no need for discharge self-locking maintenance, that is, there is no need to switch the switch module 12 to be in the second state of discharge circuit conduction.

[0132] When comparator U2B determines that the third voltage divider signal is less than the fourth voltage divider signal, it means that the main battery BAT2 has sufficient power, and the output of comparator U2B outputs a low level, and the discharge self-locking module 132 starts working. Specifically, when the third voltage divider signal is less than the fourth voltage divider signal, the output of comparator U2B outputs a low level through diode D5 to the base of transistor Q3 in the discharge self-locking module 132. Since the emitter of transistor Q3 is connected to the power supply voltage VCC, transistor Q3 is turned on, which means that the discharge self-locking module 132 starts to operate in the discharge self-locking state.

[0133] Furthermore, the common terminal COM (pin 3) and normally closed terminal NC (pin 5) of the switch RLY1 are in the default closed state. Before the discharge button SW1 is pressed, pins 3-5 of the switch RLY1 are closed. When the third voltage divider signal is less than the fourth voltage divider signal and the main battery BAT2 has sufficient power, the discharge self-locking module 132 starts to work. If the switch module 12 receives a discharge signal at this time, that is, the discharge button SW1 is pressed and in the conducting state, since the discharge button SW1 is connected to the main battery BAT2, when the discharge button SW1 is conducting, it provides the working voltage to the base of transistor Q4, thereby turning on transistor Q4. The conducting transistor Q4 pulls down the base voltage of transistor Q3, causing transistor Q3 to conduct, thus forming a VCC / Q3 / R23 / VBAT2 / R24 / GND path, thereby keeping the base of transistor Q4 at a high level. This keeps the base of transistor Q5 at a high level, thus keeping Q5 constantly conducting. Consequently, transistor Q5 continuously outputs a low level to the switch RLY1. This keeps the common terminal COM (pin 3) and normally open terminal (pin 4) of the relay in switch RLY1 closed, providing a discharge self-locking function. This means that the discharge circuit between the main battery BAT2 and the load remains connected. Even if the discharge button SW1 is released, as long as the comparator U2B determines that the third voltage divider signal is less than the fourth voltage divider signal, the main battery BAT2 will continue to supply power to the load.

[0134] Furthermore, during the discharge process of the main battery BAT2, when the main battery BAT2 is discharged to insufficient power, when the third voltage divider signal is greater than the fourth voltage divider signal, the output of the comparator U2B outputs a high level, which is then transmitted to the base of the transistor Q3 through the diode D5. The transistor Q3 is turned off, and the transistors Q4 and Q5 do not work. The discharge self-locking module 132 does not work. At this time, the transistor Q5 will not output a low level signal to the switch RLY1. The switch RLY1 returns to the original closed state of the common terminal COM (pin 3) and the normally closed terminal NC (pin 5), that is, the discharge circuit between the main battery BAT2 and the load is disconnected.

[0135] In one exemplary embodiment, such as Figure 7As shown, the charge / discharge control circuit also includes an automatic switch drive module 17. The automatic switch drive module 17 is connected to the first voltage divider module 14, the second voltage divider module 15, and the discharge control module 13. The first voltage divider module 14 is used to connect to the backup battery BAT1 and acquire the first voltage divider signal, and the second voltage divider module 15 is used to connect to the main battery BAT2 and acquire the second voltage divider signal. The automatic switch drive module 17 is used to automatically control the discharge control module 13 to achieve automatic switching between the first state and the second state based on the comparison result of the first voltage divider signal and the second voltage divider signal.

[0136] like Figure 8 As shown, the automatic switch drive module 17 includes a comparator U3C and a diode D7. The non-inverting input of comparator U3C and the inverting input of comparator U2A in the charging control module 11 are connected to the same point as the second voltage divider module 15, meaning the non-inverting input of comparator U3C also receives the second voltage divider signal. The inverting input of comparator U3C and the non-inverting input of comparator U2A in the charging control module 11 are connected to the same point as the first voltage divider module 14, meaning the inverting input of comparator U3C also receives the first voltage divider signal. The output of comparator U3C is connected to the anode of diode D7, and the cathode of diode D7 is connected to the input of the discharge self-locking module 132 of the discharge control module 13. The input of the discharge self-locking module 132 is the base of transistor Q4. Therefore, comparator U3C controls the switching of the state of the discharge control module 13 based on the first and second voltage divider signals.

[0137] It is worth noting that, as mentioned earlier, during the charging process of the main battery BAT2, when the user presses the discharge button SW1, regardless of whether the battery is fully charged, the switch RLY1 will switch from a state where the common terminal COM (pin 3) and the normally closed terminal NC (pin 5) are connected to a state where the common terminal COM (pin 3) and the normally open terminal N are connected. O (4-pin) Connection status: When the discharge button SW1 is pressed, the charging circuit is disconnected, and the discharge circuit of the main battery BAT2 and the load is switched to the conducting state.

[0138] In this embodiment, an automatic switch drive module 17 is included, which enables the main battery BAT2 to be fully charged, thereby controlling the discharge button SW1 to be automatically pressed, achieving the process of automatic discharge upon full charge. The specific implementation principle is as follows:

[0139] When the main battery BAT2 is fully charged, the second voltage divider signal is greater than the first voltage divider signal, the non-inverting input of comparator U3C is greater than the inverting input, and the output of comparator U3C outputs a high-level signal to the input of the discharge self-locking module 132 of the discharge control module 13. That is, the output of comparator U3C outputs a high-level signal to the base of transistor Q4 of the discharge self-locking module 132. When the high-level input reaches the base of transistor Q4, the output of the discharge self-locking module 132 outputs a low-level signal to the switching switch RLY1 of the switching module 12. That is, the transistor Q5 of the discharge self-locking module 132 outputs a low-level signal to the switching switch RLY1 of the switching module 12. At this time, the common terminal COM and the normally open terminal NO of the switching switch RLY1 are closed, that is, the discharge circuit between the main battery BAT2 and the load is connected. Therefore, after the main battery BAT2 is fully charged, the automatic switching drive module 17 can realize the automatic switching of the discharge circuit and realize the discharge process.

[0140] In some embodiments, such as Figure 9 As shown, the charge / discharge control circuit includes a resistor R8 and a light-emitting diode LED2. The first end of resistor R8 is connected to the first end of resistor R7, and the second end of resistor R8 is connected to the anode of LED2. The cathode of LED2 is grounded. The first end of resistor RL is connected to the first end of resistor R8, and the second end of resistor RL is grounded (GND).

[0141] When the switching module 12 connects the discharge circuit between the main battery BAT2 and the load resistor RL, the LED lights up. When the switching module 12 disconnects the connection between the main battery BAT2 and the load resistor RL, and connects the charging circuit between the main battery BAT2 and the backup battery BAT1, the LED turns off.

[0142] In one exemplary embodiment, an electrical device is provided, which includes a main battery, a backup battery, and the charge / discharge control circuit described in the above embodiment.

[0143] The charging and discharging control circuit in the charging device includes: a charging control module for connecting a backup battery; a switching module for connecting the charging control module and a main battery that supplies power to the load, the switching module being in either a first state or a second state, wherein the first state is a charging circuit for connecting the charging control module and the main battery to supply power to the main battery via the backup battery, and the second state is a discharging circuit for connecting the main battery and the load; a discharging control module is connected to the main battery and the switching module; the charging control module is used to cut off the charging circuit when the main battery is charged to a first preset voltage; the switching module is used to activate the discharging control module when a discharging signal is received, the activated discharging control module is used to control the switching module to switch from the first state to the second state; the activated discharging control module is also used to detect the voltage of the main battery during the main battery discharge process, and is used to maintain the second state of the switching module when the voltage of the main battery is greater than the second preset voltage, and is also used to control the switching module to switch from the second state to the first state when the voltage of the main battery is less than the second preset voltage.

[0144] This embodiment of the application, through the cooperation between the charging control module, the switching module, and the discharging control module, can automatically switch to the backup battery to charge the main battery when the main battery is low in power. After the main battery is fully charged, the main battery will then supply power to the load, thus solving the problem of insufficient battery power.

[0145] In the description of this specification, references to terms such as "some embodiments," "other embodiments," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative descriptions of the above terms do not necessarily refer to the same embodiments or examples.

[0146] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0147] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of this application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these modifications and improvements all fall within the protection scope of this application. Therefore, the protection scope of this application should be determined by the appended claims.

Claims

1. A charge-discharge control circuit characterized by comprising: The application relates to a charging and discharging control circuit, comprising: a charging control module for connecting a backup battery; a switch module for connecting the charging control module and a main battery for powering a load, the switch module being used in a first state or a second state, wherein the first state is a charging loop for connecting the charging control module and the main battery to power the main battery with the backup battery, and the second state is a discharging loop for connecting the main battery and the load; a discharging control module for connecting the main battery and the switch module; the charging control module is used for cutting off the connection with the switch module to disconnect the charging loop when the main battery is charged to a first preset voltage; and the switch module is used for starting the discharging control module when a discharging signal is received; the discharging control module comprises an electric quantity detection module and a discharging self-locking module, the electric quantity detection module is connected with the main battery and used for detecting the electric quantity in the discharging process of the main battery, and the discharging self-locking module is connected with the electric quantity detection module and the switch module; when the electric quantity detection module detects that the voltage of the main battery is greater than a second preset voltage and the switch module receives a discharging signal, a starting signal is sent to the discharging self-locking module, and the started discharging self-locking module is used for controlling the switch module to switch from the first state to the second state; when the electric quantity detection module detects that the voltage of the main battery is greater than the second preset voltage, the electric quantity detection module outputs a maintaining signal to the discharging self-locking module, and the discharging self-locking module is used for maintaining the second state of the switch module; when the electric quantity detection module detects that the voltage of the main battery is less than the second preset voltage, the electric quantity detection module outputs a switching signal to the discharging self-locking module, and the discharging self-locking module is used for controlling the switch module to switch from the second state to the first state.

2. The charge and discharge control circuit according to claim 1, characterized by, The charging and discharging control circuit further comprises a first voltage division module for connecting the backup battery and a second voltage division module for connecting the main battery; the charging control module comprises a comparison module and a switch module, the control end of the switch module, the first voltage division module and the second voltage division module are respectively connected with the output end of the comparison module, the first input end of the comparison module and the second input end of the comparison module, and the output end of the switch module is connected with the backup battery and the switch module; the first voltage division module is used for obtaining a first voltage division signal, the second voltage division module is used for obtaining a second voltage division signal, and the comparison module is used for outputting a connecting signal and a disconnecting signal to the control end of the switch module according to the comparison result of the first voltage division signal and the second voltage division signal; the connecting signal is used for controlling the switch module to connect to turn on the switch module and the switch module to turn on the charging loop of the backup battery and the main battery, and the disconnecting signal is used for controlling the switch module to disconnect to cut off the switch module and the switch module to disconnect the charging loop of the backup battery and the main battery.

3. The charge and discharge control circuit according to claim 2, characterized by, The comparison module comprises a comparator U2A, a resistor R9, a resistor R12, a resistor R13 and a diode D3; The non-inverting input terminal of the comparator U2A is connected with the first voltage dividing module and the first end of the resistor R9 respectively, the inverting input terminal of the comparator U2A is connected with the second voltage dividing module, the second end of the resistor R9 is connected with the anode of the diode D3, the cathode of the diode D3 is connected with the output terminal of the comparator U2A; the first end of the resistor R13 is connected with the output terminal of the comparator U2A, the second end of the resistor R13 is connected with the control terminal of the switch module, and the first end of the resistor R13 is also connected with the power voltage through the resistor R12.

4. The charge and discharge control circuit according to claim 2, characterized by, The switch module comprises a switch tube Q1, a triode Q2, a resistor R3, a resistor R6 and a light emitting diode LED1; The control terminal of the switch tube Q1 is connected with the first end of the resistor R3 and the first end of the resistor R6, the first end of the switch tube Q1 is connected with the second end of the resistor R3 and the standby battery, and the second end of the switch tube Q1 is connected with the switch module; The base of the triode Q2 is connected with the output terminal of the comparison module, the emitter of the triode Q2 is grounded, and the collector of the triode Q2 is connected with the cathode of the light emitting diode LED1; The second end of the resistor R6 is connected with the anode of the light emitting diode LED1.

5. The charge and discharge control circuit according to claim 1, wherein The charge and discharge control circuit further comprises a first voltage dividing module and a third voltage dividing module; the power detection module comprises a comparator U2B, The output terminal, the non-inverting input terminal and the inverting input terminal of the comparator U2B are connected with the discharge self-locking module, the first voltage dividing module and the third voltage dividing module respectively; the first voltage dividing module is used for connecting the standby battery and obtaining a third voltage dividing signal, and the third voltage dividing module is used for connecting the main battery and obtaining a fourth voltage dividing signal; The comparator U2B is used for outputting the switching signal to the discharge self-locking module when the third voltage dividing signal is greater than the fourth voltage dividing signal; and the comparator U2B is used for outputting the maintaining signal to the discharge self-locking module when the third voltage dividing signal is less than the fourth voltage dividing signal.

6. The charge and discharge control circuit according to claim 1, wherein The discharge self-locking module comprises a first control module, a second control module and a third control module; The control terminal of the first control module is connected with the discharge signal receiving port of the switch module, the first end of the first control module is connected with the control terminal of the second control module, and the second end of the first control module is grounded; the first end of the second control module is connected with the power voltage, the control terminal of the third control module is connected with the second end of the switch module and the second control module, the first end of the third control module is connected with the state switching port of the switch module, and the second end of the third control module is grounded; When the power detection module detects that the voltage of the main battery is greater than the second preset voltage, the power detection module outputs the starting signal to the control terminal of the second control module, so as to start the discharge self-locking module. When the discharge self-locking module is started and the switching switch module receives a discharge signal, the discharge signal is used to control the first control module to be turned on, the turned-on first control module is used to control the second control module and the third control module to be turned on, and the turned-on third control module is used to output a low-level signal to a state switching port of the switching switch module, so as to control the switching switch module to switch to the second state; In the process of discharging the main battery, when the power detection module detects that the voltage of the main battery is greater than the second preset voltage, the power detection module outputs a maintaining signal to the second control module, and the first control module and the second control module maintain being turned on to maintain the third control module to be turned on, so as to control the third control module to continuously output a low-level signal to the state switching port of the switching switch module; In the process of discharging the main battery, when the power detection module detects that the voltage of the main battery is less than the second preset voltage, the power detection module outputs a switching signal to a control end of the second control module, and the switching signal is used to control the second control module and the third control module to be turned off, and the switching switch module is recovered from the second state to the first state.

7. The charge and discharge control circuit according to claim 6, wherein The first control module comprises a triode Q4 and a resistor R24. The base of the triode Q4 is connected with the first end of the resistor R24, the third control module and the switching switch module respectively, the emitter of the triode Q4 is grounded, and the collector of the triode Q4 is connected with the second control module. The second end of the resistor R24 is grounded.

8. The charge and discharge control circuit according to claim 6, wherein The second control module comprises a triode Q3, a resistor R20, a resistor R21 and a capacitor C1. The base of the triode Q3 is connected with the first end of the resistor R20 and the first end of the resistor R21, the emitter of the triode Q3 is connected with a power supply voltage, and the collector of the triode Q3 is connected with the third control module. The second end of the resistor R20 is connected with the power supply voltage. The second end of the resistor R21 is connected with the first control module. The first end of the capacitor C1 is connected with the power supply voltage, and the second end of the capacitor C1 is connected with the first control module.

9. The charge and discharge control circuit according to claim 6, wherein The second control module comprises a triode Q5, a resistor R22, a resistor R23 and a diode D6. The base of the triode Q5 is connected with the first end of the resistor R22, the emitter of the triode Q5 is grounded, and the collector of the triode Q5 is connected with the switching switch module. The second end of the resistor R22 is connected with the first end of the resistor R23 and the cathode of the diode D6 respectively, the second end of the resistor R23 is connected with the switching switch module, and the anode of the diode D6 is grounded. The switching switch module comprises a switching switch RLY1, a discharge button SW1 and a diode D4.

10. The charge and discharge control circuit according to any one of claims 1 to 9, characterized by, The first end of the discharge button SW1 is connected with the first end of the main battery, and the second end of the discharge button SW1 is connected with the second end of the main battery through the diode D4. ​ The switch RLY1 is used to connect the first end of the main battery, the discharge control module, the charge control module and the load end; The discharge button SW1 is used to provide working voltage for the discharge control module to start the discharge control module when receiving the discharge signal; The starting of the discharge control module is used to control the switch RLY1 to connect the main battery and the load end; when the voltage of the main battery is greater than the second preset voltage, the discharge control module is used to maintain the switch RLY1 in the state of connecting the main battery and the load end; when the voltage of the main battery is less than the second preset voltage, the discharge control module is used to control the switch RLY1 to switch from the state of connecting the main battery and the load end to the state of connecting the main battery and the charge control module.

11. The charge and discharge control circuit according to any one of claims 1 to 9, characterized by, The charge and discharge control circuit further comprises a first voltage division module, a second voltage division module and a switch automatic driving module, and the switch automatic driving module is connected with the first voltage division module, the second voltage division module and the discharge control module; The first voltage division module is used to connect the standby battery and obtain a first voltage division signal, the second voltage division module is used to connect the main battery and obtain a second voltage division signal, and the switch automatic driving module is used to automatically control the discharge control module to realize automatic switching between the first state and the second state according to the comparison result of the first voltage division signal and the second voltage division signal.

12. An electrical device, characterized by The power consumption device comprises a main battery, a standby battery and a charge and discharge control circuit according to any one of claims 1-11.

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