Lead-acid battery voltage adaptive charging circuit, charging method and charger

Abstract

The present invention relates to the technical field of lead-acid battery charging, and discloses a voltage-adaptive charging circuit, charging method, and charger for lead-acid batteries. The charging circuit includes a control board, an amplifier circuit connected to the control board, a conduction control circuit, and a charging voltage generating circuit. The control board is provided with an output terminal for a pulse control signal, which is connected to the negative electrode of the lead-acid battery to be charged via the amplifier circuit and the conduction control circuit connected in sequence. The conduction control circuit is used to intermittently output the amplified pulse control signal, which is used to repair a lead-acid battery to be charged that has sulfation. The control board controls the charging voltage generating circuit to adjust the output charging voltage based on feedback voltage. The present invention first charges with a pulse current to restore the activity of the lead-acid battery and normalize the battery voltage, repairing a partially sulfated lead-acid battery. The invention can accurately detect the battery voltage to provide a more suitable charging voltage to complete charging, thereby extending the service life of the lead-acid battery.

Description

Technical Field

[0001] The present invention relates to the technical field of lead-acid battery charging, and in particular to a lead-acid battery voltage adaptive charging circuit, a charging method and a charger. Background Art

[0002] Lead-acid batteries (VRLA) are batteries with electrodes primarily made of lead and its oxides and an electrolyte consisting of sulfuric acid. They are widely used in a variety of fields, including automotive, communications, electric vehicles, and mobile audio systems. Currently, sulfation in lead-acid batteries is a major factor in reducing battery capacity and lifespan.

[0003] In existing technology, adaptive voltage chargers for lead-acid batteries adapt to the battery voltage by first detecting the battery voltage and then automatically adjusting it to the appropriate voltage. Because the voltage is detected first, incorrect voltage detection may occur for sulfated lead-acid batteries, resulting in charging failure. Summary of the Invention

[0004] Technical purpose: In response to the above technical problems, the present invention discloses a lead-acid battery voltage adaptive charging circuit, charging method and charger, which can accurately detect the battery voltage to provide a more matching charging voltage to complete charging.

[0005] Technical solution: To achieve the above technical objectives, the present invention adopts the following technical solution:

[0006] A voltage-adaptive charging circuit for a lead-acid battery, characterized by comprising a control board, an amplifier circuit connected to the control board, a conduction control circuit, and a charging voltage generating circuit; the output end of the charging voltage generating circuit is connected to the positive electrode of the lead-acid battery to be charged, and is used to provide an adaptive charging voltage under the control of the control board; the control board is provided with an output end for a pulse control signal, which is connected to the negative electrode of the lead-acid battery to be charged via the amplifier circuit and the conduction control circuit connected in sequence; the conduction control circuit is used to intermittently output the amplified pulse control signal, and the pulse control signal is used to repair the lead-acid battery to be charged that has sulfation.

[0007] The conduction control circuit and the negative electrode of the lead-acid battery are both provided with detection resistors for sending voltage feedback signals to the control board. The control board controls the charging voltage generating circuit to adjust the output charging voltage according to the feedback voltage.

[0008] Specifically, it also includes a control board connector for installing the control board, a rechargeable battery connector for installing the positive and negative electrodes of the rechargeable battery, and a DC power supply for providing working current for the amplification circuit and the conduction control circuit;

[0009] The rechargeable battery connector has three pins, wherein pin one of the rechargeable battery connector serves as the positive electrode connection terminal of the rechargeable battery, and pin three serves as the negative electrode connection terminal of the rechargeable battery;

[0010] The control board connector has ten pins, pin three of the control board connector is connected to the pulse control signal output by the control board; pin one of the control board connector and pin three of the rechargeable battery connector are connected via a sixteenth resistor; pin two of the control board connector is connected to the positive pole of the DC power supply, and pin ten is grounded;

[0011] The amplifying circuit includes a twelfth resistor, a third transistor, a nineteenth resistor, a fourteenth capacitor, and a seventeenth resistor; pin three of the control board connector is connected to the base of the third transistor via the twelfth resistor, the emitter and base of the third transistor are connected to the nineteenth resistor, and the common connection point of the base and the nineteenth resistor is connected to ground via the fourteenth capacitor;

[0012] The conduction control circuit includes a field-effect transistor, a shunt, a twelfth capacitor, a fifteenth resistor, a thirteenth capacitor, and an eighteenth resistor. The gate of the field-effect transistor is connected to the collector of the third transistor via the seventeenth resistor, and the pulse control signal amplified by the third transistor is used to control the intermittent conduction of the field-effect transistor. The drain of the field-effect transistor is connected to pin three of the rechargeable battery connector, and the source is grounded via the shunt. The two ends of the twenty-first resistor are respectively connected to the drain and source of the field-effect transistor and a common connection point of the shunt. The twelfth capacitor is connected in series with the fifteenth resistor and then connected in parallel with the twenty-first resistor. The common connection point of the field-effect transistor and the seventeenth resistor is grounded via a filter circuit composed of the thirteenth capacitor and the eighteenth resistor.

[0013] The voltage across the twenty-first resistor and the sixteenth resistor is transmitted to the control board as a feedback voltage, and the control board adapts the corresponding charging voltage according to the feedback voltage.

[0014] Specifically, the charging voltage generating circuit includes a transformer, and a seventh diode, an eighth diode and a ninth capacitor are provided in parallel on the secondary side of the transformer, and the cathodes of the seventh diode and the eighth diode are both connected to pin 1 of the charging battery connector.

[0015] The present invention also discloses a charging method of a lead-acid battery voltage adaptive charging circuit, which is characterized by sequentially executing the following steps:

[0016] S1, the control board sends an intermittent control signal to the base of the third transistor, controlling the intermittent conduction of the third transistor, thereby controlling the intermittent conduction of the field effect tube to connect the charging circuit, thereby generating a pulse current; charging with the pulse current restores the activity of the lead-acid battery and restores the battery voltage to normal voltage;

[0017] S2. Detect the battery voltage. The control board selects the charging voltage of the lead-acid battery according to the detected battery voltage and charges the lead-acid battery.

[0018] The invention also discloses a lead-acid battery charger, which is characterized by comprising the lead-acid battery voltage adaptive charging circuit.

[0019] Beneficial effects: Due to the adoption of the above technical solution, the present invention has the following technical effects:

[0020] (1) The charging method of the present invention first charges with a pulse current, which can effectively restore the activity of the lead-acid battery and restore the battery voltage to normal voltage, repair the lead-acid battery that has been partially sulfated, and extend the effective service life of the lead-acid battery;

[0021] (2) The charging method of the present invention ensures the accuracy of battery voltage detection by effectively recovering and detecting batteries that have been stored for too long or whose electrodes have been sulfurized and are unloaded, or whose voltage is low. Then, the control circuit reasonably selects the charging voltage based on the recovered battery voltage adapter to complete the charging of the lead-acid battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a structural block diagram of the lead-acid battery voltage adaptive charging circuit of the present invention;

[0023] Figure 2 A circuit diagram of an embodiment of a voltage adaptive charging circuit for a lead-acid battery according to the present invention;

[0024] Figure 3 for Figure 1 Circuit diagram of the battery pulse repair circuit;

[0025] The control board connector is CN3, the rechargeable battery connector is CN2; the sixteenth resistor is R16, the twelfth resistor is R12, the third transistor is Q3, the nineteenth resistor is R19, the fourteenth capacitor is C14, and the seventeenth resistor is R17; the field effect transistor is Q6, the shunt is RS1, the twelfth capacitor is C12, the fifteenth resistor is R15, the thirteenth capacitor is C13, and the eighteenth resistor is R18.

[0026] Transformer-T1, seventh diode-D7, eighth diode-D8, ninth capacitor-C9; ninth diode-D9, tenth capacitor-C11, eleventh capacitor-C11, tenth diode-D10;

[0027] The 22nd resistor R22, the 23rd resistor R23, the 15th capacitor C15, the 20th resistor R20, the 16th capacitor C16, the 24th resistor R24, the 25th resistor R25; the 17th capacitor C17, the 26th resistor R26, the 27th resistor R27, the 11th diode R11, the 18th capacitor C18, the 19th capacitor C19, the 20th capacitor C20, the Zener diode U4, the 28th resistor R28, the 29th resistor R29, the 30th resistor R30, the 31st resistor R31, the 32nd resistor R32, the 21st capacitor C21, and IC U3. DETAILED DESCRIPTION

[0028] The present invention will be described in detail below with reference to the accompanying drawings.

[0029] like Figures 1 to 2 As shown, the present invention discloses a new circuit based on first performing pulse charging to repair the battery and then detecting the battery voltage, including a control board, an amplifier circuit connected to the control board, a conduction control circuit, a charging voltage generating circuit, a control board connector CN3 for installing the control board, a rechargeable battery connector CN2 for installing the positive and negative poles of the rechargeable battery, and a DC power supply for providing working current to the amplifier circuit and the conduction control circuit.

[0030] like Figure 2 and Figure 3 As shown, in this embodiment, the rechargeable battery connector CN2 has three pins, pin 1 of the rechargeable battery connector CN2 serves as the positive electrode connection terminal of the rechargeable battery, and pin 3 serves as the negative electrode connection terminal of the rechargeable battery;

[0031] The control board connector CN3 has ten pins. Pin 3 of the control board connector CN3 is connected to the pulse control signal output by the control board. Pin 1 of the control board connector CN3 and pin 3 of the rechargeable battery connector CN2 are connected via a sixteenth resistor R16. Pin 2 of the control board connector is connected to the positive pole of the DC power supply, and pin 10 is grounded.

[0032] The amplifier circuit comprises a twelfth resistor R12, a third transistor Q3, a nineteenth resistor R19, a fourteenth capacitor C14, and a seventeenth resistor R17. Pin 3 of the control board connector is connected to the base of the third transistor Q3 via the twelfth resistor R12. The emitter and base of the third transistor Q3 are connected to the nineteenth resistor R19, and the common connection point between the base and the nineteenth resistor R19 is connected to ground via the fourteenth capacitor C14.

[0033] The conduction control circuit comprises a field-effect transistor Q6, a shunt RS1, a twelfth capacitor C12, a fifteenth resistor R15, a thirteenth capacitor C13, and an eighteenth resistor R18. The gate of the field-effect transistor Q6 is connected to the collector of the third transistor Q3 via the seventeenth resistor R17. The pulse control signal amplified by the third transistor Q3 is used to control the intermittent conduction of the field-effect transistor Q6. The drain of the field-effect transistor Q6 is connected to pin 3 of the rechargeable battery connector, and the source is connected to ground via the shunt RS1. The two ends of the twenty-first resistor R21 are respectively connected to the common connection point of the drain and source of the field-effect transistor Q6 and the shunt RS1. The twelfth capacitor C12 and the fifteenth resistor R15 are connected in series and then in parallel with the twenty-first resistor. The common connection point of the field-effect transistor Q6 and the seventeenth resistor R17 is connected to ground via a filter circuit formed by the thirteenth capacitor C13 and the eighteenth resistor R18.

[0034] The voltage across the twenty-first resistor R21 and the sixteenth resistor R16 is used as a feedback voltage and transmitted to the control board.

[0035] The charging voltage generating circuit comprises a transformer T1. A seventh diode D7, an eighth diode D8, and a ninth capacitor C9 are connected in parallel on the secondary side of transformer T1. The cathodes of diodes D7 and D8 are connected to pin 1 of rechargeable battery connector CN2. In the charging circuit of the present invention, transformer T1 operates in a switching power supply mode, generating an output voltage. However, the charging current loop is controlled by field-effect transistor Q6. Pulse current charging is achieved by intermittently controlling the base of Q3 with an intermittent control signal from the control board, thereby controlling the intermittent conduction of Q3 and thus Q6, which connects the charging loop and generates pulsed charging current.

[0036] In the present invention, the control board can be a single chip microcomputer or a self-designed control circuit board, which includes an output terminal for outputting a pulse control signal. Transformer T1 is a component of the charging power supply (switching power supply), and T1 can be designed or selected separately according to the power of the charging power supply (switching power supply). Figure 2As shown, this embodiment also includes a constant current control circuit for a charging power supply, i.e., a switching power supply. The working principle of the charging circuit of the present invention is as follows: After the battery charger is turned on and connected to the battery to be charged, the pin 3 of CN3 receives the pulse control signal sent by the control board, passes through the resistor R12 to the base of the transistor Q3, passes through the emitter of the transistor Q3 to the collector, amplifies the pulse signal, passes through R17 to the gate of the field effect transistor Q6, and controls the intermittent conduction of the field effect transistor Q6. The charging current generated by the charger passes through D8 to the pin 1 of CN2, which is connected to the positive electrode of the battery to be charged, and then passes through the negative electrode of the battery to be charged to the pin 3 of CN2, and then passes through the drain of the field effect transistor Q6 to the source, and then passes through the charging current. The current flows through the shunt S1 and reaches the negative pole of the charging power supply, giving a pulse charging current to the battery to be charged. The control board controls the pulse charging time. After a period of pulse charging, the sulfidation reaction of the lead-acid battery electrode is eliminated and the normal voltage of the lead-acid battery is restored (12V battery is restored to 10V, 24V battery is restored to 20V). The voltage is fed back to the control board through R16 and R21, that is, through the resistor R21 and RS1 to the ground, which serves as the detection ground. The positive voltage is detected by the resistor R16 and transmitted to the control board. After the control board detects the battery voltage, it adapts the reasonable charging voltage to charge the battery.

[0037] The charging method of the lead-acid battery voltage adaptive charging circuit comprises the following steps:

[0038] S1. Charge with pulse current to restore the activity of the lead-acid battery and restore the battery voltage to normal voltage, such as restoring a 12V battery to 10V and a 24V battery to 20V;

[0039] S2. Detect the battery voltage, select the charging voltage of the lead-acid battery according to the detected battery voltage, and charge the lead-acid battery.

[0040] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A charging method for a lead-acid battery voltage adaptive charging circuit, characterized in that: The lead-acid battery voltage adaptive charging circuit includes a control board, an amplifier circuit connected to the control board, a conduction control circuit, and a charging voltage generating circuit. The output end of the charging voltage generating circuit is connected to the positive electrode of the lead-acid battery to be charged, and is used to provide an adaptive charging voltage under the control of the control board. The control board is provided with an output end for a pulse control signal, and the pulse control signal is connected to the negative electrode of the lead-acid battery to be charged via the amplifier circuit and the conduction control circuit connected in sequence. The conduction control circuit is used to intermittently output the amplified pulse control signal, and the pulse control signal is used to repair the lead-acid battery to be charged that has sulfation. The conduction control circuit and the negative electrode of the lead-acid battery are both provided with a detection resistor for sending a voltage feedback signal to the control board, and the control board controls the charging voltage generating circuit to adjust the output charging voltage according to the feedback voltage; The lead-acid battery voltage adaptive charging circuit further includes a control board connector (CN3) for mounting a control board, a rechargeable battery connector (CN2) for mounting positive and negative electrodes of a lead-acid battery, and a DC power supply for providing operating current to an amplifier circuit and a conduction control circuit; wherein the rechargeable battery connector (CN2) has three pins, wherein pin 1 of the rechargeable battery connector (CN2) serves as a positive electrode connection terminal of the lead-acid battery, and pin 3 serves as a negative electrode connection terminal of the lead-acid battery; the control board connector (CN3) has ten pins, wherein pin 3 of the control board connector (CN3) is connected to a pulse control signal output by the control board; pin 1 of the control board connector (CN3) and pin 3 of the rechargeable battery connector (CN2) are connected via a sixteenth resistor (R16); pin 2 of the control board connector is connected to the positive electrode of the DC power supply, and pin 10 is grounded; The amplifier circuit includes a twelfth resistor (R12), a third transistor (Q3), a nineteenth resistor (R19), a fourteenth capacitor (C14) and a seventeenth resistor (R17); pin three of the control board connector (CN3) is connected to the base of the third transistor (Q3) via the twelfth resistor (R12); the emitter and base of the third transistor (Q3) are connected to the nineteenth resistor (R19); and a common connection point between the base and the nineteenth resistor (R19) is grounded via the fourteenth capacitor (C14); The conduction control circuit comprises a field effect tube (Q6), a shunt (RS1), a twelfth capacitor (C12), a fifteenth resistor (R15), a thirteenth capacitor (C13) and an eighteenth resistor (R18); the gate of the field effect tube (Q6) is connected to the collector of the third triode (Q3) via the seventeenth resistor (R17); the pulse control signal amplified by the third triode (Q3) is used to control the intermittent conduction of the field effect tube (Q6); the drain of the field effect tube (Q6) is connected to the collector of the rechargeable battery connector (CN2) Pin 3, the source of the field effect transistor (Q6) is grounded via a shunt (RS1); two ends of a twenty-first resistor (R21) are respectively connected to the drain and source of the field effect transistor (Q6) and a common connection point of the shunt (RS1); a twelfth capacitor (C12) and a fifteenth resistor (R15) are connected in series and then connected in parallel with the twenty-first resistor (R21); a common connection point of the gate of the field effect transistor (Q6) and a seventeenth resistor (R17) is grounded via a filter circuit consisting of a thirteenth capacitor (C13) and an eighteenth resistor (R18); The voltage across the twenty-first resistor (R21) and the sixteenth resistor (R16) is transmitted to the control board as a feedback voltage, and the control board adapts the corresponding charging voltage according to the feedback voltage; The charging method performs the following steps in sequence: S1, the control board sends an intermittent control signal to the base of the third transistor (Q3), controlling the intermittent conduction of the third transistor (Q3), thereby controlling the intermittent conduction of the field effect transistor (Q6) to connect the charging circuit, thereby generating a pulse current; the pulse current is used to charge the lead-acid battery, restore the activity of the lead-acid battery, and restore the battery voltage to normal voltage; S2. Detect the battery voltage. The control board selects the charging voltage of the lead-acid battery according to the detected battery voltage and charges the lead-acid battery.

2. A lead-acid battery voltage adaptive charging circuit, implementing the charging method of claim 1, characterized in that: The lead-acid battery voltage adaptive charging circuit includes a control board, an amplifier circuit connected to the control board, a conduction control circuit, and a charging voltage generating circuit. The output end of the charging voltage generating circuit is connected to the positive electrode of the lead-acid battery to be charged, and is used to provide an adaptive charging voltage under the control of the control board. The control board is provided with an output end for a pulse control signal, and the pulse control signal is connected to the negative electrode of the lead-acid battery to be charged via the amplifier circuit and the conduction control circuit connected in sequence. The conduction control circuit is used to intermittently output the amplified pulse control signal, and the pulse control signal is used to repair the lead-acid battery to be charged that has sulfation. The conduction control circuit and the negative electrode of the lead-acid battery are both provided with a detection resistor for sending a voltage feedback signal to the control board, and the control board controls the charging voltage generating circuit to adjust the output charging voltage according to the feedback voltage; The lead-acid battery voltage adaptive charging circuit further includes a control board connector (CN3) for mounting a control board, a rechargeable battery connector (CN2) for mounting positive and negative electrodes of a lead-acid battery, and a DC power supply for providing operating current to an amplifier circuit and a conduction control circuit; wherein the rechargeable battery connector (CN2) has three pins, wherein pin 1 of the rechargeable battery connector (CN2) serves as a positive electrode connection terminal of the lead-acid battery, and pin 3 serves as a negative electrode connection terminal of the lead-acid battery; the control board connector (CN3) has ten pins, wherein pin 3 of the control board connector (CN3) is connected to a pulse control signal output by the control board; pin 1 of the control board connector (CN3) and pin 3 of the rechargeable battery connector (CN2) are connected via a sixteenth resistor (R16); pin 2 of the control board connector is connected to the positive electrode of the DC power supply, and pin 10 is grounded; The amplifier circuit includes a twelfth resistor (R12), a third transistor (Q3), a nineteenth resistor (R19), a fourteenth capacitor (C14) and a seventeenth resistor (R17); pin three of the control board connector (CN3) is connected to the base of the third transistor (Q3) via the twelfth resistor (R12); the emitter and base of the third transistor (Q3) are connected to the nineteenth resistor (R19); and a common connection point between the base and the nineteenth resistor (R19) is grounded via the fourteenth capacitor (C14); The conduction control circuit comprises a field effect tube (Q6), a shunt (RS1), a twelfth capacitor (C12), a fifteenth resistor (R15), a thirteenth capacitor (C13) and an eighteenth resistor (R18); the gate of the field effect tube (Q6) is connected to the collector of the third triode (Q3) via the seventeenth resistor (R17); the pulse control signal amplified by the third triode (Q3) is used to control the intermittent conduction of the field effect tube (Q6); the drain of the field effect tube (Q6) is connected to the collector of the rechargeable battery connector (CN2) Pin 3, the source of the field effect transistor (Q6) is grounded via a shunt (RS1); two ends of a twenty-first resistor (R21) are respectively connected to the drain and source of the field effect transistor (Q6) and a common connection point of the shunt (RS1); a twelfth capacitor (C12) and a fifteenth resistor (R15) are connected in series and then connected in parallel with the twenty-first resistor (R21); a common connection point of the gate of the field effect transistor (Q6) and a seventeenth resistor (R17) is grounded via a filter circuit consisting of a thirteenth capacitor (C13) and an eighteenth resistor (R18); The voltage across the twenty-first resistor (R21) and the sixteenth resistor (R16) is transmitted to the control board as a feedback voltage, and the control board adapts the corresponding charging voltage according to the feedback voltage.

3. The lead-acid battery voltage adaptive charging circuit according to claim 2, characterized in that: The charging voltage generating circuit comprises a transformer (T1), wherein a seventh diode (D7), an eighth diode (D8) and a ninth capacitor (C9) connected in parallel are provided on the secondary side of the transformer (T1), and the negative electrodes of the seventh diode (D7) and the eighth diode (D8) are both connected to pin 1 of the charging battery connector (CN2).

4. A lead-acid battery charger, characterized in that: The lead-acid battery voltage adaptive charging circuit comprises any one of claims 2-3.

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