CN201383689Y - A charger circuit - Google Patents

Abstract

The utility model discloses a charger circuit, it is including a pair of charging terminal, charge control circuit, discharge control circuit, electric current size detection circuitry, discharge electric current size detection circuitry, operation controller, lithium cell balanced circuit. A pair of charging terminals consisting of a positive charging terminal and a negative charging terminal, the plurality of batteries being inserted in series and connected thereto; the charging control circuit outputs a charging voltage; the discharging control circuit consumes the residual electric quantity on the battery; the operation controller controls the charging control circuit, the discharging control circuit, the current magnitude detection circuit, the discharging current magnitude detection circuit and the lithium battery balancing circuit to work so as to complete the charging operation process; the lithium battery balancing circuit is connected between the positive charging terminal and the charging control circuit, and the lithium battery balancing circuit can basically keep the voltages at two ends of each lithium battery which is serially connected and placed between the pair of charging terminals consistent under the control of the operation controller, so that the overall use quality of the lithium battery pack is improved.

Description

A charger circuit

[technical field]

The utility model relates to a charger circuit, in particular to a lithium battery charger circuit.

[Background technique]

Lithium-ion batteries have no memory effect, so they are ideal rechargeable batteries. When a lithium-ion battery is used as a power battery, it is generally necessary to connect multiple lithium-ion batteries in series to achieve the required voltage. Because the existing lithium-ion battery charger does not control the voltage of each battery connected in series, after charging, the performance indicators of each single battery cannot be guaranteed to be completely consistent. And so on, the charge retention capacity of the lithium-ion battery pack is significantly reduced, which affects the overall quality of use of the lithium-ion battery pack and shortens its service life. Therefore, it is necessary to provide a charger capable of keeping the performance indicators of each single-cell lithium-ion battery consistent after charging, so as to solve the shortcomings of the prior art.

[utility model content]

The utility model overcomes the shortcomings of the above-mentioned technologies, and provides a charger that controls the voltage of each battery connected in series during charging, and keeps the performance indicators of each battery consistent after charging. The charger improves the overall performance of the lithium-ion battery pack. Use quality.

In order to achieve the above object, the utility model adopts the following technical solutions:

A charger circuit comprising:

A pair of charging terminals consisting of a positive charging terminal and a negative charging terminal, to which multiple batteries are inserted in series and connected;

A charging control circuit that outputs charging voltage;

A discharge control circuit consumes the remaining power on the battery;

A charging current detection circuit;

A discharge current detection circuit;

- An operation controller to control the charging operation process;

A lithium battery balancing circuit, connected between the positive charging terminal and the charging control circuit, the lithium battery balancing circuit, under the control of the operation controller, can make each lithium battery placed in series between a pair of charging terminals The voltage across the battery remains basically the same.

A kind of charger circuit as above is characterized in that the lithium battery balancing circuit comprises:

A voltage detection circuit, which detects the voltage at both ends of each lithium battery, compares the voltage with the set rated voltage and outputs the comparison result to the operation controller;

A voltage adjustment circuit, which adjusts the voltage at both ends of each lithium battery, so that the voltage at both ends of each lithium battery is basically consistent;

An energy balance control circuit, under the control of the operation controller, starts the voltage adjustment circuit to work.

A charger circuit as described above is characterized in that the voltage detection circuit is composed of a plurality of voltage detection units, and the voltage detection units are connected to both ends of the lithium battery.

A charger circuit as described above is characterized in that the voltage detection unit includes a voltage comparator, the positive input terminal of the voltage comparator is connected to the positive pole of the lithium battery through a resistor, and the negative input terminal of the voltage comparator is connected to the positive electrode of the lithium battery through a resistor. The negative pole of the lithium battery is connected, and the output terminal of the voltage comparator is connected with the operation controller through a resistor.

A charger circuit as described above is characterized in that the voltage detection unit includes a voltage comparator N2B, the positive input terminal of the voltage comparator N2B is connected to the negative pole of the lithium battery through a resistor, and the negative input terminal of the voltage comparator N2B is connected through The resistor is connected to the positive pole of the lithium battery, the output terminal of the voltage comparator N2B is connected to the gate of the MOSFET tube, the drain of the MOSFET tube is connected to the negative input terminal of the voltage comparator N2B, and the source terminal of the MOSFET tube is connected to the operation control The source of the MOSFET tube is grounded through a resistor at the same time.

A charger circuit as described above is characterized in that the voltage detection unit includes a resistor, one end of which is connected to the positive pole of the lithium battery, and the other end is connected to the operation controller.

A charger circuit as described above is characterized in that the voltage adjustment circuit is composed of a plurality of voltage adjustment units, and the voltage adjustment units are connected to the energy balance control circuit and connected to the positive pole of the lithium battery.

A charger circuit as described above is characterized in that the voltage adjustment unit is composed of two branches, the branch includes a first MOSFET tube, a second MOSFET tube, a third MOSFET tube, and the source of the first MOSFET tube It is connected to the output terminal of the charging control circuit, the drain of the first MOSFET is connected to one end of the resistor and the drain of the second MOSFET, the gate of the first MOSFET is connected to the other end of the resistor and the gate of the second MOSFET connection, the source of the second MOSFET is connected to the positive pole of the lithium battery, the source of the third MOSFET is connected to the gate of the second MOSFET through a resistor, the drain of the third MOSFET is grounded, and the gate of the third MOSFET The pole is connected with the operation controller, and a resistor is connected between the drain and the gate of the third MOSFET tube.

A charger circuit as described above is characterized in that the voltage adjustment unit is composed of two branches, the branch includes a first MOSFET tube, a second MOSFET tube, a third MOSFET tube, a fourth MOSFET tube, the first The source of the MOSFET is connected to the output terminal of the charging control circuit, the drain of the first MOSFET is connected to one end of the resistor and the drain of the second MOSFET, and the gate of the first MOSFET is connected to the other end of the resistor and the second The gate of the MOSFET is connected, the source of the second MOSFET is connected to the positive electrode of the lithium battery, the source of the third MOSFET is connected to the gate of the second MOSFET through a resistor, and the drain of the third MOSFET is connected to the 18V power supply , a resistor is connected between the drain and the gate of the third MOSFET, the gate of the third MOSFET is connected to the source of the fourth MOSFET, the drain of the fourth MOSFET is grounded, and the gate of the fourth MOSFET The pole is connected with the operation controller, and a resistor is connected between the drain and the gate of the fourth MOSFET tube.

A charger circuit as described above is characterized in that the energy balance control circuit includes a transformer with multiple secondary windings, one end of the primary winding of the transformer is connected to the source of a switch MOSFET Q4, and the switch MOSFET Q4 The drain is grounded, the gate of the switching MOSFET Q4 is connected to the operation controller through a resistor, the other end of the primary winding of the transformer is connected to the source of the first MOSFET of a branch of each voltage adjustment unit, each of the transformers One end of the secondary winding is respectively connected to the source of the first MOSFET of the other branch of each voltage adjustment unit.

The beneficial effects of the utility model are: due to the adoption of the lithium battery balancing circuit connected between the positive charging terminal and the charging control circuit, the lithium battery balancing circuit can compare the charging voltage of each single-cell lithium battery with the set voltage. The rated voltage is compared, and the comparison result is output to the operation controller; under the control of the operation controller, the lithium battery balancing circuit adjusts the voltage at both ends of each lithium battery, so that the voltage and self-discharge performance of each lithium battery are basically maintained. Consistent, the charge retention capacity of the lithium-ion battery pack is significantly improved, the overall quality of use of the lithium-ion battery pack is enhanced, and the service life is improved.

[Description of drawings]

Fig. 1 is a block diagram of the utility model;

Fig. 2 is a block diagram of the internal structure of the lithium battery balancing circuit of the present utility model;

Fig. 3 is the schematic circuit diagram of the utility model.

[Detailed ways]

Below in conjunction with accompanying drawing and embodiment of the present utility model, further describe in detail:

As shown in Figure 1, the utility model introduces a charger circuit, which can charge nickel-cadmium batteries, nickel-hydrogen batteries, lead-acid batteries, and lithium batteries. It includes a pair of charging terminals, a charging control circuit 3, and a discharging control circuit 4 , Current size detection circuit 5, discharge current size detection circuit 6, operation controller 7, lithium battery balance circuit 8. A pair of charging terminals consists of a positive charging terminal 1 and a negative charging terminal 2, and multiple batteries are inserted in series and connected to it; the charging control circuit 3 outputs the charging voltage; the discharging control circuit 4 consumes the remaining power on the battery; charging The current size detection circuit 5 and the discharge current size detection circuit 6 respectively detect the current size of the charging and discharging process and send the detection results to the operation controller 7; the operation controller 7 controls the charging control circuit 3, the discharge control circuit 4, and the current detection circuit Circuit 5, discharge current size detection circuit 6, and lithium battery balancing circuit 8 work to complete the charging operation process; lithium battery balancing circuit 8 is connected between the positive charging terminal and charging control circuit 7, and lithium battery balancing circuit 8 Under the control of the operation controller 7 , the voltages at both ends of each lithium battery placed in series between a pair of charging terminals can be basically kept the same.

In order to introduce this patent in detail, an embodiment is given below to further describe this patent. As shown in Figures 2 and 3, the embodiment can charge 6 batteries connected in series. , a voltage regulation circuit 10, and an energy balance control circuit 11. The voltage detection circuit 9 detects the voltage at both ends of each lithium battery, compares the voltage with the set rated voltage and outputs the comparison result to the operation controller 7; the voltage adjustment circuit 10 adjusts the voltage at both ends of each lithium battery, The voltage at both ends of each lithium battery is kept basically the same; the energy balance control circuit 11 starts the voltage adjustment circuit 10 to work under the control of the operation controller 7 .

The voltage detection circuit 9 is composed of six voltage detection units 12, and the voltage detection units 12 are connected to both ends of the lithium battery. The voltage detecting unit 12 has three kinds of circuit structures, the circuit structure of the voltage detecting unit 12 at both ends of the sixth battery and the fifth battery is the same, which is the first circuit structure, and the circuit structure is as follows: including a voltage comparator N2A (N2C), a voltage comparator The positive input terminal of the voltage comparator N2A (N2C) is connected to the positive pole of the sixth (fifth) lithium battery through a resistor, and the negative input terminal of the voltage comparator N2A (N2C) is connected to the negative pole of the sixth (fifth) lithium battery through a resistor The output end of the voltage comparator N2A (N2C) is connected with the pin AD6 (AD5) of the operation controller 7 through a resistor.

The circuit structure of the voltage detection unit 12 at both ends of the fourth battery, the third battery, and the second battery is the same, which is the second circuit structure. The circuit structure is as follows: the voltage detection unit 12 includes a voltage comparator N2B (N2D, N3B), The positive input terminal of the voltage comparator N2B (N2D, N3B) is connected to the negative pole of the fourth (third, second) lithium battery through a resistor, and the negative input terminal of the voltage comparator N2B (N2D, N3B) is connected to the negative electrode of the fourth lithium battery through a resistor. The positive poles of four (third and second) lithium batteries are connected, the output terminal of the voltage comparator N2B (N2D, N3B) is connected to the gate of the MOSFET tube, and the drain of the MOSFET tube is connected to the voltage comparator N2B (N2D, N3B) The reverse input terminal is connected, the source of the MOSFET is connected to the pin AD4 (AD3, AD2) of the operation controller 7, and the source of the MOSFET is grounded through a resistor at the same time.

The voltage detection unit 12 at both ends of the first battery is a third circuit structure, including a resistor, one end of which is connected to the positive pole of the lithium battery, and the other end is connected to the pin AD1 of the operation controller 7 .

The voltage adjustment circuit 10 is composed of six voltage adjustment units 13, and the voltage adjustment units 13 are connected to the energy balance control circuit 11 and connected to the positive pole of the lithium battery. The voltage adjustment unit 13 has two kinds of circuit structures, wherein, the circuit structure of the voltage adjustment unit 13 connected to the sixth to the third battery is the same, which is the first circuit structure, and the structure is as follows: the voltage adjustment unit 13 is composed of two branches , the branch includes a first MOSFET, a second MOSFET, and a third MOSFET, the source of the first MOSFET is connected to the output of the charging control circuit 3, the drain of the first MOSFET is connected to one end of the resistor and The drain of the second MOSFET is connected, the gate of the first MOSFET is connected to the other end of the resistor and the gate of the second MOSFET, the source of the second MOSFET is connected to the positive pole of the lithium battery, and the gate of the third MOSFET The source is connected to the gate of the second MOSFET through a resistor, the drain of the third MOSFET is grounded, and the gate of the third MOSFET is connected to the operation controller 7, between the drain and the gate of the third MOSFET There is a resistor connected. The circuit structure of the voltage adjustment unit 13 connected to the second to the first battery is the same, it is a second circuit structure, and the structure is as follows: the voltage adjustment unit 13 is composed of two branches, and the branch includes a first MOSFET tube, a second Two MOSFET tubes, a third MOSFET tube, and a fourth MOSFET tube, the source of the first MOSFET tube is connected to the output terminal of the charging control circuit 3, the drain of the first MOSFET tube is connected to one end of the resistor and the drain of the second MOSFET tube connection, the gate of the first MOSFET is connected to the other end of the resistor and the gate of the second MOSFET, the source of the second MOSFET is connected to the positive electrode of the lithium battery, and the source of the third MOSFET is connected to the second resistor through the resistor. The gate of the MOSFET is connected, the drain of the third MOSFET is connected to the 18V power supply, a resistor is connected between the drain and the gate of the third MOSFET, the gate of the third MOSFET is connected to the source of the fourth MOSFET connected, the drain of the fourth MOSFET is grounded, the gate of the fourth MOSFET is connected to the operation controller 7, and a resistor is connected between the drain and the gate of the fourth MOSFET.

The energy balance control circuit 11 includes a transformer with multiple secondary windings, one end of the primary winding of the transformer is connected to the source of a switch MOSFET Q4, the drain of the switch MOSFET Q4 is grounded, and the gate of the switch MOSFET Q4 passes through The resistance is connected with the operation controller 7, the other end of the primary winding of the transformer is connected with the source of the first MOSFET tube of a branch of each voltage adjustment unit 13, and one end of each secondary winding of the transformer is respectively connected with each voltage The source of the first MOSFET tube of the other branch of the adjustment unit 13 is connected.

Claims (10)

1, a kind of charger circuit comprises:

The a pair of charging terminal that an anodal charging terminal (1) and a negative pole charging terminal (2) are formed, multiple batteries are connected to be inserted and is connected thereto;

A charging control circuit (3), the output charging voltage;

A charge/discharge control circuit (4) consumes dump energy on the battery;

A charging current size detection circuit (5);

A discharging current size detection circuit (6);

One operation control (7), control charging operations process;

It is characterized in that,

A lithium battery balancing circuitry (8) is connected between described anodal charging terminal and the charging control circuit (7), lithium battery balancing circuitry (8) can be under the control of operation control (7), and the lithium battery both end voltage that respectively saves that makes series connection be placed between a pair of charging terminal is consistent substantially.

2, a kind of charger circuit according to claim 1 is characterized in that lithium battery balancing circuitry (8) comprising:

One voltage detecting circuit (9) detects the both end voltage respectively save lithium battery, the rated voltage of this voltage and setting is compared and comparative result is exported to operation control (7);

One voltage-regulating circuit (10) is adjusted the both end voltage that respectively saves lithium battery, makes that respectively saving the lithium battery both end voltage is consistent substantially;

One energy balance control circuit (11), under the control of operation control (7), starting resistor is adjusted circuit (10) and is carried out work.

3, a kind of charger circuit according to claim 2 is characterized in that voltage detecting circuit (9) is made of a plurality of voltage detection units (12), and voltage detection unit (12) is connected the two ends of lithium battery.

4, a kind of charger circuit according to claim 3, it is characterized in that voltage detection unit (12) comprises voltage comparator (N2A), the positive input of voltage comparator (N2A) is connected with the positive pole of lithium battery by resistance, the reverse input end of voltage comparator (N2A) is connected by the negative pole of resistance with this joint lithium battery, and the output of voltage comparator (N2A) is connected with operation control (7) by resistance.

5, a kind of charger circuit according to claim 3, it is characterized in that voltage detection unit (12) comprises voltage comparator (N2B), the positive input of voltage comparator (N2B) is connected with the negative pole of lithium battery by resistance, the reverse input end of voltage comparator (N2B) is connected by the positive pole of resistance with this joint lithium battery, the output of voltage comparator (N2B) is connected with the grid of MOSFET pipe, the drain electrode of MOSFET pipe is connected with the reverse input end of voltage comparator (N2B), the source electrode of MOSFET pipe is connected with operation control (7), and the source electrode of MOSFET pipe passes through grounding through resistance simultaneously.

6, a kind of charger circuit according to claim 3 is characterized in that voltage detection unit (12) comprises a resistance, and the one end is connected with the positive pole of lithium battery, and the other end is connected with operation control (7).

7, a kind of charger circuit according to claim 2, it is characterized in that voltage-regulating circuit (10) is made of a plurality of voltage-adjusting units (13), voltage-adjusting unit (13) is connected with energy balance control circuit (11), and is connected on the positive pole of lithium battery.

8, a kind of charger circuit according to claim 7, it is characterized in that voltage-adjusting unit (13) is made of two branch roads, this branch road includes MOSFET pipe, the 2nd MOSFET pipe, the 3rd MOSFET pipe, the source electrode of the one MOSFET pipe is connected with the output of charging control circuit (3), the drain electrode of the one MOSFET pipe is connected with an end of resistance and the drain electrode of the 2nd MOSFET pipe, the grid of the one MOSFET pipe is connected with the grid of the other end of resistance and the 2nd MOSFET pipe, the source electrode of the 2nd MOSFET pipe is connected with the positive pole of lithium battery, the source electrode of the 3rd MOSFET pipe is connected by the grid of resistance with the 2nd MOSFET pipe, the grounded drain of the 3rd MOSFET pipe, the grid of the 3rd MOSFET pipe is connected with operation control (7), is connected with resistance between the drain and gate of the 3rd MOSFET pipe.

9, a kind of charger circuit according to claim 7, it is characterized in that voltage-adjusting unit (13) is made of two branch roads, this branch road includes MOSFET pipe, the 2nd MOSFET pipe, the 3rd MOSFET pipe, the 4th MOSFET pipe, the source electrode of the one MOSFET pipe is connected with the output of charging control circuit (3), the drain electrode of the one MOSFET pipe is connected with an end of resistance and the drain electrode of the 2nd MOSFET pipe, the grid of the one MOSFET pipe is connected with the grid of the other end of resistance and the 2nd MOSFET pipe, the source electrode of the 2nd MOSFET pipe is connected with the positive pole of lithium battery, the source electrode of the 3rd MOSFET pipe is connected by the grid of resistance with the 2nd MOSFET pipe, the drain electrode of the 3rd MOSFET pipe connects the 18V power supply, between the drain and gate of the 3rd MOSFET pipe, be connected with resistance, the grid of the 3rd MOSFET pipe is connected with the source electrode of the 4th MOSFET pipe, the grounded drain of the 4th MOSFET pipe, the grid of the 4th MOSFET pipe is connected with operation control (7), is connected with resistance between the drain and gate of the 4th MOSFET pipe.

10, according to Claim 8 or 9 described a kind of charger circuits, it is characterized in that energy balance control circuit (11) includes with a plurality of secondary transformers, one end of the elementary winding of this transformer is connected with the source electrode that a switch MOS FET manages (Q4), the grounded drain of switch MOS FET pipe (Q4), the grid of switch MOS FET pipe (Q4) is connected with operation control (7) by resistance, the other end of the elementary winding of transformer is connected with the source electrode of a MOSFET pipe of a branch road of each voltage-adjusting unit (13), and an end of each secondary winding of transformer is connected with the source electrode of a MOSFET pipe of another branch road of each voltage-adjusting unit (13) respectively.

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