A multi-cell lithium battery circuit with 0V charging inhibition

Abstract

The present invention discloses a multi-cell lithium battery circuit with 0V charging prohibition, comprising a charging and discharging terminal, a battery protection circuit, a 0V charging prohibition circuit and a lithium battery, wherein the charging and discharging terminal is connected to the battery protection circuit, the battery protection circuit is also connected to the 0V charging prohibition circuit and the lithium battery respectively, the 0V charging prohibition circuit is also connected to the lithium battery, the charging and discharging terminal receives the voltage and transmits it to the battery protection circuit, the 0V charging prohibition circuit collects the voltage signal of the lithium battery and controls the action of the battery protection circuit according to the voltage signal, and the present invention can control the protection circuit to cut off the charging circuit after the lithium battery voltage is lower than the prohibition charging voltage value, prohibit charging the lithium battery, realize the 0V charging prohibition function, and achieve the effect of maintaining the safety and stability of the lithium battery. The circuit does not require software control and has the characteristics of low cost, low power consumption, small voltage drop and high safety.

Description

Technical Field

[0001] The invention relates to the technical field of batteries, in particular to a multi-cell lithium battery circuit with 0V charging inhibition. Background Art

[0002] Among various electronic products, many products are powered by lithium batteries. Due to the chemical characteristics of lithium batteries, when the lithium battery is discharged to 0V and then charged, irreversible chemical changes will occur inside the lithium battery, which will affect the stability of the lithium battery and even cause the risk of explosion. Most lithium battery manufacturers will set a prohibited charging voltage value. Therefore, adding a lithium battery 0V prohibited charging function to the circuit can greatly increase the safety of lithium batteries during use. Summary of the invention

[0003] The object of the present invention is to provide a multi-cell lithium battery circuit with 0V charging inhibition to solve the problems raised in the above background technology.

[0004] To achieve the above object, the present invention provides the following technical solutions:

[0005] A multi-cell lithium battery circuit with 0V charging inhibition includes charging and discharging terminals, a battery protection circuit, a 0V charging inhibition circuit and a lithium battery, wherein the charging and discharging terminals are connected to the battery protection circuit, the battery protection circuit is also connected to the 0V charging inhibition circuit and the lithium battery respectively, the 0V charging inhibition circuit is also connected to the lithium battery, the charging and discharging terminals receive voltage and transmit it to the battery protection circuit, and the 0V charging inhibition circuit collects voltage signals of the lithium battery and controls the action of the battery protection circuit according to the voltage signals.

[0006] As a further technical solution of the present invention: the charging and discharging terminal includes an interface J1, the battery protection circuit includes a chip U1, a switch tube Q1, a switch tube Q2, a capacitor C13 and a capacitor C14, a 0V charging prohibition circuit includes a resistor R19, a resistor R20 and a switch tube Q5, one end of the interface J1 is connected to a capacitor C8 and a fuse F1, the other end of the capacitor C8 is connected to a capacitor C9, the other end of the capacitor C9 is connected to the cathode of the diode D2, the anode of the diode DZ4, the resistor R6, the capacitor C13, the other end of the interface J1 and the source of the switch tube Q2, the fuse F1 The other end of the resistor R1 is connected to the anode of the diode D1, the resistor R2 and the positive electrode of the battery B3. The cathode of the diode D1 is connected to the resistor R1. The other end of the resistor R1 is connected to the capacitor C1, the cathode of the diode DZ1, the voltage VDD and the pin 16 of the chip U1. The other end of the resistor R2 is connected to the capacitor C2 and the pin 15 of the chip U1. The negative electrode of the battery B3 is connected to the positive electrode of the battery B2 and the resistor R3. The other end of the resistor R3 is connected to the capacitor C3 and the pin 14 of the chip U1. The negative electrode of the battery B2 is connected to the positive electrode of the battery B1 and the resistor R4. The other end of the resistor R4 is connected to the capacitor C4 and pin 13 of chip U1, the negative electrode of battery B0 is connected to the anode of diode DZ1, resistor Rs1, the other end of capacitor C1, the other end of capacitor C2, the other end of capacitor C3, the other end of capacitor C4, resistor RT1 and capacitor C10, pin 1 of chip U1 is connected to the drain of switch tube Q5 through resistor R11, the gate of switch tube Q5 is connected to resistor R19 and resistor R20, the other end of resistor R19 is connected to the source of switch tube Q5 and voltage VDD, the other end of resistor R20 is grounded, the other end of resistor Rs1 is connected to the anode of diode DZ3, Resistor R5, capacitor C14 and the source of the switch tube Q1, pin 4 of the chip U1 is connected to the drain of the switch tube Q1 and the drain of the switch tube Q2 through a resistor R17, pin 2 of the chip U1 is connected to the anode of the diode D2 through a resistor R15, pin 3 of the chip U1 is connected to the other end of the resistor R6, the cathode of the diode ZD4 and the gate of the switch tube Q2 through a resistor R16, the other end of the capacitor C13 is connected to the other end of the capacitor C14, and pin 5 of the chip U1 is connected to the other end of the resistor R5, the cathode of the diode DZ3 and the gate of the switch tube Q1 through a resistor R18.

[0007] As a further technical solution of the present invention: the switch tube Q5 is a P-channel field effect tube or a triode.

[0008] As a further technical solution of the present invention: the resistor RT1 is a thermistor.

[0009] As a further technical solution of the present invention: the model of the chip U1 is SH367103.

[0010] As a further technical solution of the present invention: the battery B1, battery B2 and battery B3 are all lithium batteries.

[0011] As a further technical solution of the present invention: the switch tube Q1 is a MOS tube.

[0012] As a further technical solution of the present invention: the switch tube Q2 is a MOS tube.

[0013] As a further technical solution of the present invention: the voltage VDD is a battery sampling voltage, and the resistor R19 and the resistor R20 form a resistor voltage divider circuit.

[0014] As a further technical solution of the present invention: the diode ZD1, the diode DZ3 and the diode DZ4 are all voltage stabilizing diodes.

[0015] Compared with the prior art, the invention has the following beneficial effects: the invention can control the protection circuit to cut off the charging circuit after the lithium battery voltage is lower than the prohibited charging voltage value, prohibit the charging of the lithium battery, realize the 0V charging prohibition function, and achieve the effect of maintaining the safety and stability of the lithium battery. The circuit does not require software control and has the characteristics of low cost, low power consumption, small voltage drop, and high safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of the invention structure;

[0017] Figure 2 This is a circuit diagram of the present invention. DETAILED DESCRIPTION

[0018] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0019] See also Figure 1-2 Embodiment 1, a multi-cell lithium battery circuit with 0V charging prohibition, comprising charging and discharging terminals, a battery protection circuit, a 0V charging prohibition circuit and a lithium battery, wherein the charging and discharging terminals are connected to the battery protection circuit, the battery protection circuit is also connected to the 0V charging prohibition circuit and the lithium battery respectively, the 0V charging prohibition circuit is also connected to the lithium battery, the charging and discharging terminals receive voltage and transmit it to the battery protection circuit, the 0V charging prohibition circuit collects the voltage signal of the lithium battery and controls the action of the battery protection circuit according to the voltage signal.

[0020] As a further technical solution of the present invention: the charging and discharging terminal includes an interface J1, the battery protection circuit includes a chip U1, a switch tube Q1, a switch tube Q2, a capacitor C13 and a capacitor C14, the 0V charging prohibition circuit includes a resistor R19, a resistor R20 and a switch tube Q5, one end of the interface J1 is connected to the capacitor C8 and the fuse F1, the other end of the capacitor C8 is connected to the capacitor C9, the other end of the capacitor C9 is connected to the cathode of the diode D2, the anode of the diode DZ4, the resistor R6, the capacitor C13, the other end of the interface J1 and the source of the switch tube Q2, the other end of the fuse F1 Connect the anode of diode D1, resistor R2 and the positive electrode of battery B3, the cathode of diode D1 is connected to resistor R1, the other end of resistor R1 is connected to capacitor C1, the cathode of diode DZ1, voltage VDD and pin 16 of chip U1, the other end of resistor R2 is connected to capacitor C2 and pin 15 of chip U1, the negative electrode of battery B3 is connected to the positive electrode of battery B2 and resistor R3, the other end of resistor R3 is connected to capacitor C3 and pin 14 of chip U1, the negative electrode of battery B2 is connected to the positive electrode of battery B1 and resistor R4, the other end of resistor R4 is connected to capacitor C4 and pin 14 of chip U1 13. The negative electrode of the battery B0 is connected to the anode of the diode DZ1, the resistor Rs1, the other end of the capacitor C1, the other end of the capacitor C2, the other end of the capacitor C3, the other end of the capacitor C4, the resistor RT1 and the capacitor C10. The pin 1 of the chip U1 is connected to the drain of the switch tube Q5 through the resistor R11. The gate of the switch tube Q5 is connected to the resistor R19 and the resistor R20. The other end of the resistor R19 is connected to the source of the switch tube Q5 and the power supply terminal VDD. The other end of the resistor R20 is grounded. The source of the switch tube Q5 is connected to the voltage VDD. The other end of the resistor Rs1 is connected to the diode DZ3. The anode of the chip U1, the resistor R5, the capacitor C14 and the source of the switch tube Q1, the pin 4 of the chip U1 is connected to the drain of the switch tube Q1 and the drain of the switch tube Q2 through the resistor R17, the pin 2 of the chip U1 is connected to the anode of the diode D2 through the resistor R15, the pin 3 of the chip U1 is connected to the other end of the resistor R6, the cathode of the diode ZD4 and the gate of the switch tube Q2 through the resistor R16, the other end of the capacitor C13 is connected to the other end of the capacitor C14, and the pin 5 of the chip U1 is connected to the other end of the resistor R5, the cathode of the diode DZ3 and the gate of the switch tube Q1 through the resistor R18. The switch tube Q5 can be replaced by a PNP transistor; the U1 model is the SH367103 series chip.

[0021] Pin1 of chip U1 in the battery protection circuit is CTL. When the pin is at VDD level, U1 controls Q1 and Q2 in the normal protection state; when the pin is floating or at GND level, U1 controls Q1 and Q2 in the disconnected state; since Vgs(th) of the P-channel field effect transistor Q5 is -1.3V, when the voltage difference between the G pole and the S pole of Q5 is lower than -1.3V, the D and S poles of the P-channel field effect transistor Q5 are turned on, otherwise the D and S poles of Q5 are disconnected.

[0022] When the battery voltage is normal, the Vgs of Q5 after voltage division by R19 and R20 is less than -1.3V. At this time, Q5 is in the on state, the Pin1 CTL voltage of U1 is equal to VDD, and the battery protection circuit is in normal working state.

[0023] When the battery voltage drops to the prohibited charging voltage value, the Vgs of Q5 after the voltage division by R19 and R20 is greater than -1.3V. At this time, Q5 is in the disconnected state, Pin1 CTL of U1 is in the floating state, U1 controls Q1 and Q2 in the disconnected state, and the entire battery cannot be charged or discharged.

[0024] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other specific forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations falling within the meaning and scope of the equivalent elements of the claims be included in the invention. Any reference numeral in a claim should not be considered as limiting the claim to which it relates.

[0025] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A multi-cell lithium battery circuit with 0V charging inhibition, comprising a charging and discharging terminal, a battery protection circuit, a 0V charging inhibition circuit and a lithium battery, characterized in that: The charge and discharge terminals are connected to the battery protection circuit, which is also connected to the 0V charge prohibition circuit and the lithium battery respectively, and the 0V charge prohibition circuit is also connected to the lithium battery. The charge and discharge terminals receive the voltage and transmit it to the battery protection circuit, and the 0V charge prohibition circuit collects the voltage signal of the lithium battery and controls the action of the battery protection circuit according to the voltage signal; The charge and discharge terminal includes an interface J1, a battery protection circuit includes a chip U1, a switch tube Q1, a switch tube Q2, a capacitor C13 and a capacitor C14, a 0V charging prohibition circuit includes a resistor R19, a resistor R20 and a switch tube Q5, one end of the interface J1 is connected to a capacitor C8 and a fuse F1, the other end of the capacitor C8 is connected to a capacitor C9, the other end of the capacitor C9 is connected to a cathode of a diode D2, an anode of a diode DZ4, a resistor R6, a capacitor C13, the other end of the interface J1 and a source of the switch tube Q2, the other end of the fuse F1 is connected to an anode of a diode D1, a resistor R19, a capacitor C20 and a source of a diode DZ4. R2 and the positive electrode of battery B3, the cathode of diode D1 is connected to resistor R1, the other end of resistor R1 is connected to capacitor C1, the cathode of diode DZ1, voltage VDD and pin 16 of chip U1, the other end of resistor R2 is connected to capacitor C2 and pin 15 of chip U1, the negative electrode of battery B3 is connected to the positive electrode of battery B2 and resistor R3, the other end of resistor R3 is connected to capacitor C3 and pin 14 of chip U1, the negative electrode of battery B2 is connected to the positive electrode of battery B1 and resistor R4, the other end of resistor R4 is connected to capacitor C4 and pin 13 of chip U1, the negative electrode of battery B0 is connected The anode of the diode DZ1, the resistor Rs1, the other end of the capacitor C1, the other end of the capacitor C2, the other end of the capacitor C3, the other end of the capacitor C4, the resistor RT1 and the capacitor C10, the pin 1 of the chip U1 is connected to the drain of the switch tube Q5 through the resistor R11, the gate of the switch tube Q5 is connected to the resistor R19 and the resistor R20, the other end of the resistor R19 is connected to the source of the switch tube Q5 and the voltage VDD, the other end of the resistor R20 is grounded, the other end of the resistor Rs1 is connected to the anode of the diode DZ3, the resistor R5, the capacitor C14 and the source of the switch tube Q1, the chip U Pin 4 of chip U1 is connected to the drain of switch tube Q1 and the drain of switch tube Q2 through resistor R17, pin 2 of chip U1 is connected to the anode of diode D2 through resistor R15, pin 3 of chip U1 is connected to the other end of resistor R6, the cathode of diode DZ4 and the gate of switch tube Q2 through resistor R16, the other end of capacitor C13 is connected to the other end of capacitor C14, pin 5 of chip U1 is connected to the other end of resistor R5, the cathode of diode DZ3 and the gate of switch tube Q1 through resistor R18; the switch tube Q1 is a MOS tube; the switch tube Q2 is a MOS tube.

2. A multi-cell lithium battery circuit with 0V charging inhibition according to claim 1, characterized in that: The switch tube Q5 is a P-channel field effect tube or a triode.

3. A multi-cell lithium battery circuit with 0V charging inhibition according to claim 2, characterized in that: The resistor RT1 is a thermistor.

4. A multi-cell lithium battery circuit with 0V charging inhibition according to claim 2, characterized in that: The model of the chip U1 is SH367103.

5. A multi-cell lithium battery circuit with 0V charging inhibition according to claim 2, characterized in that: The battery B1, battery B2 and battery B3 are all lithium batteries.

6. A multi-cell lithium battery circuit with 0V charging inhibition according to claim 2, characterized in that: The voltage VDD is the battery sampling voltage, and the resistor R19 and the resistor R20 form a resistor voltage divider circuit; the diode ZD1, 二 The diode DZ3 and the diode DZ4 are both voltage-stabilizing diodes.

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