CN104158155A

CN104158155A - Balancing protection circuit for lithium battery

Info

Publication number: CN104158155A
Application number: CN201410388950.6A
Authority: CN
Inventors: 黄国文; 杨圣峯; 何鹏; 彭建普
Original assignee: Guangxi Zhuo Neng New Energy Technology Co Ltd
Current assignee: Guangxi Zhuo Neng New Energy Technology Co Ltd
Priority date: 2014-08-08
Filing date: 2014-08-08
Publication date: 2014-11-19
Anticipated expiration: 2034-08-08
Also published as: CN104158155B

Abstract

The invention relates to a balancing protection circuit for a lithium battery. The circuit comprises a sampling circuit, a balancing circuit, an under-voltage protection circuit, comparison circuits, a driving circuit, first reference voltage, second reference voltage, supply voltage and a state output circuit, wherein each comparison circuit is used for comparing the first reference voltage and the second reference voltage with the corresponding sampling battery voltage of the lithium battery respectively, and outputting a first level signal; the state output circuit is used for outputting a second level signal according to the first level signals output by all the comparison circuits; the driving circuit is used for determining whether to output a driving signal to a corresponding balancing circuit or not according to the second level signal and the corresponding first level signal; the balancing circuit is used for controlling the connection of the positive pole and the negative pole of the corresponding lithium battery according to the corresponding driving signal so as to discharge the corresponding lithium battery. The balancing protection circuit has the advantage of low manufacture cost.

Description

The balanced protection circuit of lithium battery

Technical field

The present invention relates to the protective circuit technology of lithium battery, be specifically related to the protective circuit technology of multi-series lithium battery.

Background technology

On market, the protective circuit of multi-string lithium ion battery has following situation now:

1. hardware Acquisition Circuit and MCU control;

2. the IC of string more than single gathers and controls;

3. many single-unit cascade IC gather and control;

Scheme 1 software and hardware combining, has increased the complexity of circuit, with high costs; Scheme 2 is confined to the function of IC, joint number is restricted (although its maximum can detect the series connection of n batteries, but might not can use from 2-n joint), or the end balance of can only charging (just starting balancing circuitry under the fast full condition of single battery); Scheme 3 is that cost is high equally, or only has end equilibrium function.

Because the consensus of cell in lithium ion battery bag causes cell to overcharge and after condition to one's heart's content; protective circuit on market just can be processed for the smaller problem of monomer battery voltage pressure reduction; long-term accumulation; monomer battery voltage pressure reduction will increase gradually; after whole charge and discharge process completes; battery does not still reach the balance of voltage; the balancing circuitry of multi-string lithium ion battery bag circuit protection plate was lost efficacy gradually; the power output of battery strings reduces simultaneously, and shorten the useful life of power brick.

Summary of the invention

The object of the invention is to propose a kind of balanced protection circuit of lithium battery, it can the high problem of workout cost.

In order to achieve the above object, the technical solution adopted in the present invention is as follows:

A kind of balanced protection circuit of lithium battery, the quantity of described lithium battery is at least two, and all lithium batteries are connected in series, described balanced protection circuit comprises: all and sample circuit, balancing circuitry, under-voltage protecting circuit, comparison circuit and the drive circuit, one first reference voltage, one second reference voltage, a supply voltage and the State-output circuit that with described lithium battery connect one to one identical with the quantity of described lithium battery;

Described sample circuit, for obtaining the sampling cell voltage of corresponding lithium battery;

Described under-voltage protecting circuit, for judging that whether the sampling cell voltage of corresponding lithium battery is greater than described the first reference voltage, if so, disconnects with corresponding balancing circuitry, if not, positive pole and the negative pole of controlling the lithium battery in corresponding balancing circuitry disconnect;

Described comparison circuit, for the first reference voltage and the second reference voltage are compared with the sampling cell voltage of corresponding lithium battery respectively, and exports one first level signal;

Described State-output circuit, for according to the first level signal of all comparison circuit outputs, exports a second electrical level signal;

Described drive circuit, for according to second electrical level signal and the first corresponding level signal, judges whether to corresponding balancing circuitry output drive signal;

Described balancing circuitry, for according to corresponding driving signal, the positive pole of controlling corresponding lithium battery is connected with negative pole, so that corresponding lithium battery is carried out to discharge process;

Described supply voltage, is used to sample circuit, under-voltage protecting circuit, comparison circuit and State-output circuit that operating voltage is provided.

The balanced protection circuit of another kind of lithium battery of the present invention, the quantity of described lithium battery is at least two, and all lithium batteries are connected in series, described balanced protection circuit comprises: all identical with the quantity of described lithium battery and control comparison circuit, a reference voltage output circuit and a supply voltage with sample circuit, balancing circuitry and under-voltage protecting circuit, at least one primary control comparison circuit, a final stage that described lithium battery connects one to one;

At least one primary control comparison circuit be designated as respectively the 1st grade of control comparison circuit, the 2nd grade of control comparison circuit ..., N level controls comparison circuit, N >=1 and be natural number; Described primary control comparison circuit comprises elementary comparison circuit, elementary the first State-output circuit, elementary the second State-output circuit, primary control circuit and first stage drive circuit; Wherein, the 1st grade of control comparison circuit provides operating voltage by described supply voltage;

Final stage is controlled comparison circuit and is comprised final stage comparison circuit, final stage State-output circuit and final driving circuit;

The quantity of elementary comparison circuit, first stage drive circuit, final stage comparison circuit and final driving circuit is all identical with the quantity of lithium battery and connect one to one with lithium battery respectively;

Described reference voltage output circuit, for output (N+2) individual reference voltage, described (N+2) individual reference voltage be designated as respectively the 1st reference voltage, the 2nd reference voltage ..., N+2 reference voltage; The 1st reference voltage < the 2nd reference voltage < ... < N+2 reference voltage;

Described under-voltage protecting circuit, for judging that whether the sampling cell voltage of corresponding lithium battery is greater than described the 1st reference voltage, if so, disconnects with corresponding balancing circuitry, if not, positive pole and the negative pole of controlling the lithium battery in corresponding balancing circuitry disconnect;

Described a plurality of primary control comparison circuit for according to the sampling cell voltage of corresponding lithium battery, judges whether to control corresponding balancing circuitry corresponding lithium battery is carried out to discharge process successively, specific as follows:

Described the 1st grade of control comparison circuit, for by its elementary comparison circuit, the 1st reference voltage and the 2nd reference voltage being compared with the sampling cell voltage of corresponding lithium battery respectively, and exports one the 11st elementary level signal; By its elementary first State-output circuit, according to all the 11st elementary level signals, export one the 12nd elementary level signals; By its elementary second State-output circuit, according to all the 11st elementary level signals, export one the 13rd elementary level signals; By its primary control circuit, according to the 12nd elementary level signal and the 13rd elementary level signal, judge whether first stage drive circuit output the 11st elementary driving signal to correspondence, and judge whether to provide operating voltage to the 2nd grade of control comparison circuit; By its first stage drive circuit, according to the 11st elementary driving signal and the 11st elementary level signal, judge whether to corresponding balancing circuitry output the 12nd elementary driving signal;

Described the 2nd grade of control comparison circuit, for by its elementary comparison circuit, the 2nd reference voltage and the 3rd reference voltage being compared with the sampling cell voltage of corresponding lithium battery respectively, and exports one the 21st elementary level signal; By its elementary first State-output circuit, according to all the 21st elementary level signals, export one the 22nd elementary level signals; By its elementary second State-output circuit, according to all the 21st elementary level signals, export one the 23rd elementary level signals; By its primary control circuit, according to the 22nd elementary level signal and the 23rd elementary level signal, judge whether first stage drive circuit output the 21st elementary driving signal to correspondence, and judge whether that to 3rd level, controlling comparison circuit provides operating voltage; By its first stage drive circuit, according to the 21st elementary driving signal and the 21st elementary level signal, judge whether to corresponding balancing circuitry output the 22nd elementary driving signal;

……；

Described N level is controlled comparison circuit, for by its elementary comparison circuit, N reference voltage and N+1 reference voltage being compared with the sampling cell voltage of corresponding lithium battery respectively, and exports the elementary level signal of a N1; By its elementary first State-output circuit, according to the elementary level signal of all N1, export the elementary level signal of a N2; By its elementary second State-output circuit, according to the elementary level signal of all N1, export the elementary level signal of a N3; By its primary control circuit, according to the elementary level signal of N2 and the elementary level signal of N3, judge whether to export the elementary driving signal of N1 to the first stage drive circuit of correspondence, and judge whether that to final stage, controlling comparison circuit provides operating voltage; By its first stage drive circuit, according to the elementary driving signal of N1 and the elementary level signal of N1, judge whether to export the elementary driving signal of N2 to corresponding balancing circuitry;

Described final stage is controlled comparison circuit, for by its final stage comparison circuit, N+1 reference voltage and N+2 reference voltage being compared with the sampling cell voltage of corresponding lithium battery respectively, and exports one first final stage level signal; By its final stage State-output circuit, according to all the first final stage level signals, export one second final stage level signals; By its final driving circuit, according to the second final stage level signal and the first corresponding final stage level signal, judge whether to drive signal to corresponding balancing circuitry output final stage;

Described balancing circuitry, for driving signal according to the 12nd of correspondence the elementary driving signal or the 22nd elementary driving signal or the elementary driving signal of N2 or final stage, the positive pole of controlling corresponding lithium battery is connected with negative pole, so that corresponding lithium battery is carried out to discharge process;

Described supply voltage, is used to sample circuit and under-voltage protecting circuit that operating voltage is provided.

Preferably, described sample circuit comprises the first to the 5th resistance and differential amplifier, the inverting input of differential amplifier connects with the negative pole of corresponding lithium battery by the 3rd resistance, the normal phase input end of differential amplifier connects with the positive pole of corresponding lithium battery by the 4th resistance, the normal phase input end of differential amplifier is also by the 5th grounding through resistance, the inverting input of differential amplifier is also by the first grounding through resistance, the inverting input of differential amplifier is also connected with the output of differential amplifier by the second resistance, the output of differential amplifier is exported the sampling cell voltage of corresponding lithium battery.

Preferably; described under-voltage protecting circuit comprises the 6th to the 9th resistance, operational amplifier and the first triode; the inverting input of operational amplifier connects with the sampling cell voltage of corresponding lithium battery by the 6th resistance; the normal phase input end of operational amplifier is connected with the 1st reference voltage by the 7th resistance; the output of operational amplifier is connected with the base stage of the first triode by the 8th resistance; the output of operational amplifier is also by the 9th grounding through resistance; the grounded emitter of the first triode, the collector electrode of the first triode is connected with the control end of balancing circuitry.

Preferably, described balancing circuitry comprises photoelectrical coupler, the the tenth to the 12 resistance and the first metal-oxide-semiconductor, the drain electrode of the first metal-oxide-semiconductor connects with the positive pole of corresponding lithium battery by the 11 resistance, the source electrode of the first metal-oxide-semiconductor connects with the negative pole of corresponding lithium battery, the transistor emitter output of photoelectrical coupler is connected with the grid of the first metal-oxide-semiconductor, the transistor emitter output of photoelectrical coupler also connects with the negative pole of corresponding lithium battery by the 12 resistance, the transistor collector input of photoelectrical coupler connects with the positive pole of corresponding lithium battery by the 11 resistance, the diode input of photoelectrical coupler is all connected with the output of the output of corresponding under-voltage protecting circuit and corresponding drive circuit.

Preferably, described elementary comparison circuit comprises the 13 to the 16 resistance, the first voltage comparator, second voltage comparator, the first diode and the second diode, the normal phase input end of the first voltage comparator is connected with N reference voltage by the 14 resistance, the inverting input of the first voltage comparator is connected with described sampling cell voltage by the 13 resistance, the inverting input of second voltage comparator is connected with N+1 reference voltage by the 16 resistance, the normal phase input end of second voltage comparator is connected with described sampling cell voltage by the 15 resistance, the anodic bonding of the output of the first voltage comparator and the first diode, the corresponding input of the negative electrode of the first diode and elementary the first State-output circuit, the corresponding input of the first input end of corresponding first stage drive circuit and elementary the second State-output circuit connects, the anodic bonding of the output of second voltage comparator and the second diode, the negative electrode of the second diode is connected with the negative electrode of the first diode.

Further preferred, described elementary the first State-output circuit comprises the first State-output electronic circuit identical with the quantity of lithium battery, each first State-output electronic circuit comprises the 17 resistance, the 18 resistance and the second triode, the base stage of the second triode connects with the output of corresponding elementary comparison circuit by the 18 resistance, the base stage of the second triode is also connected with described supply voltage by the 17 resistance, the grounded collector of the second triode, the emitter of the second triode is connected with the first input end of primary control circuit, the emitter of the second triode of one of them the first State-output electronic circuit is also connected with described supply voltage by 1 the 19 resistance,

Described elementary the second State-output circuit comprises three diode and two ten three resistance identical with the quantity of lithium battery, the 3rd triode and the 20 to the 22 resistance, each the 3rd diode forms a series arm with one the 23 corresponding resistance series connection, one end of each series arm connects with the output of corresponding elementary comparison circuit, the other end of each series arm is connected with the base stage of the 3rd triode, the base stage of the 3rd triode is by the 22 grounding through resistance, the emitter of the 3rd triode is by the 21 grounding through resistance, the emitter of the 3rd triode is connected with the second input of primary control circuit, the collector electrode of the 3rd triode is connected with described supply voltage by the 20 resistance,

Described primary control circuit comprises reduction voltage circuit, the 24 to the 37 resistance, the 3rd to the 4th metal-oxide-semiconductor, the 4th to the 6th triode, the 4th diode, the 5th diode, first to fourth electric capacity, tertiary voltage comparator and the 4th voltage comparator, described reduction voltage circuit is for being converted to a comparison voltage by described supply voltage, the inverting input of tertiary voltage comparator is connected with the described voltage of comparing by the 24 resistance, the normal phase input end of tertiary voltage comparator is connected with one end of the 25 resistance, the other end of the 25 resistance is as the second input of primary control circuit at the corresponding levels, the inverting input of the 4th voltage comparator is connected with one end of the 26 resistance, the other end of the 26 resistance is as the first input end of primary control circuit at the corresponding levels, the normal phase input end of the 4th voltage comparator by the 27 resistance with compare voltage and be connected, the output of tertiary voltage comparator is connected with the base stage of the 4th triode by the 28 resistance, the base stage of the 4th triode is by the 30 grounding through resistance, the grounded emitter of the 4th triode, the emitter of the 4th triode connects with the second input of corresponding first stage drive circuit by the first electric capacity, the collector electrode of the 4th triode is connected with the grid of the second metal-oxide-semiconductor, the collector electrode of the 4th triode is connected with the drain electrode of the second metal-oxide-semiconductor by the 31 resistance, the second input of the source electrode of the second metal-oxide-semiconductor and corresponding first stage drive circuit, the base stage of the base stage of the 4th triode and the 5th triode is all connected with the output of the 4th voltage comparator by the 29 resistance, the base stage of the 5th triode is connected with the source electrode of the 4th metal-oxide-semiconductor by the 37 resistance, the grounded collector of the 5th triode and being connected with the source electrode of the 3rd metal-oxide-semiconductor by the second electric capacity, the source electrode of the 3rd metal-oxide-semiconductor is used to the primary control comparison circuit of next stage that operating voltage is provided, the emitter of the 5th triode is connected with the drain electrode of the 3rd metal-oxide-semiconductor by the 32 resistance, the emitter of the 5th triode is connected with the grid of the 3rd metal-oxide-semiconductor, the drain electrode of the drain electrode of the second metal-oxide-semiconductor and the 3rd metal-oxide-semiconductor is all connected with the source electrode of the 4th metal-oxide-semiconductor, the drain electrode of the 4th metal-oxide-semiconductor is connected with described supply voltage, the first input end of primary control circuit at the corresponding levels is connected with the base stage of the 6th triode with the 34 resistance by the 4th diode successively, the first input end of primary control circuit at the corresponding levels is connected with the base stage of the 6th triode with the 35 resistance by the 5th diode successively, the base stage of the 6th triode is by the 36 grounding through resistance, the grounded emitter of the 6th triode and being connected with the source electrode of the 4th metal-oxide-semiconductor by the 3rd electric capacity, the collector electrode of the 6th triode is connected with the grid of the 4th metal-oxide-semiconductor, the collector electrode of the 6th triode is connected with described supply voltage by the 33 resistance,

Described just stage drive circuit, comprise the 38 to the 42 resistance, the 6th diode and the 7th triode, the collector electrode of the 7th triode is connected with one end of the 38 resistance, the other end of the 38 resistance is as the second input of first stage drive circuit, the base stage of the 7th triode is connected with the negative electrode of the 6th diode by the 39 resistance, the anode of the 6th diode is as the first input end of first stage drive circuit, the base stage of the 7th triode is by the 41 grounding through resistance, the anode of the 6th diode is by the 40 grounding through resistance, the emitter of the 7th triode is by the 42 grounding through resistance, the emitter of the 7th triode connects with the control end of corresponding balancing circuitry.

Preferably, described final stage comparison circuit comprises the 43 to the 46 resistance, the 5th voltage comparator, the 6th voltage comparator, the 7th diode and the 8th diode, the normal phase input end of the 5th voltage comparator is connected with N+1 reference voltage by the 44 resistance, the inverting input of the 5th voltage comparator is connected with described sampling cell voltage by the 43 resistance, the inverting input of the 6th voltage comparator is connected with N+2 reference voltage by the 46 resistance, the normal phase input end of the 6th voltage comparator is connected with described sampling cell voltage by the 45 resistance, the anodic bonding of the output of the 5th voltage comparator and the 7th diode, the first input end of the corresponding input of the negative electrode of the 7th diode and final stage State-output circuit and corresponding final driving circuit connects, the anodic bonding of the output of the 6th voltage comparator and the 8th diode, the negative electrode of the 8th diode is connected with the negative electrode of the 7th diode.

Further preferred, described final stage State-output circuit comprises nine diode and four ten three resistance identical with the quantity of lithium battery, the 8th triode and the 44 to the 45 resistance, each the 9th diode forms a series arm with one the 43 corresponding resistance series connection, one end of each series arm connects with the output of corresponding final stage comparison circuit, the other end of each series arm is connected with the base stage of the 8th triode, the base stage of the 8th triode is by the 45 grounding through resistance, the grounded emitter of the 8th triode and being connected with the source electrode of the 5th metal-oxide-semiconductor by the 4th electric capacity, the source electrode of the 5th metal-oxide-semiconductor is connected with the second input of final driving circuit, the collector electrode of the 8th triode is connected with described supply voltage by the 44 resistance and is connected with the drain electrode of described the 5th metal-oxide-semiconductor, the collector electrode of the 8th triode is connected with the grid of the 5th metal-oxide-semiconductor,

Described final driving circuit, comprise the 48 to the 50 resistance, the tenth diode and the 9th triode, the collector electrode of the 9th triode is connected with one end of the 48 resistance, the other end of the 48 resistance is as the second input of final driving circuit, the base stage of the 9th triode is connected with the negative electrode of the tenth diode by the 47 resistance, the anode of the tenth diode is as the first input end of final driving circuit, the base stage of the 9th triode is by the 49 grounding through resistance, the anode of the 9th diode is by the 46 grounding through resistance, the emitter of the 9th triode is by the 50 grounding through resistance, the emitter of the 9th triode connects with the control end of corresponding balancing circuitry.

The present invention has following beneficial effect:

In charging, electric discharge, standing three kinds of situations, the balance of real-time controlling lithium battery, guarantees the consistency of lithium battery voltage, thereby makes the life of lithium battery string, and volume output promotes, and has improved stability and the reliability of lithium battery string.And the present invention is without using MCU and IC, and cost is low.

Accompanying drawing explanation

Fig. 1 is the functional-block diagram of balanced protection circuit of the lithium battery of the embodiment of the present invention one;

Fig. 2 is the functional-block diagram of balanced protection circuit of the lithium battery of the embodiment of the present invention two;

Fig. 3 is the syndeton schematic diagram that in Fig. 2, the 1st grade of control comparison circuit and final stage are controlled comparison circuit;

Fig. 4 is the circuit diagram of the sample circuit of Fig. 2;

Fig. 5 is the circuit diagram of the under-voltage protecting circuit of Fig. 2;

Fig. 6 is the circuit diagram of the balancing circuitry of Fig. 2;

Fig. 7 is the circuit diagram of the elementary comparison circuit of Fig. 3;

Fig. 8 is the circuit diagram of elementary the first State-output circuit of Fig. 3;

Fig. 9 is the circuit diagram of elementary the second State-output circuit of Fig. 3;

Figure 10 is the circuit diagram of the primary control circuit of Fig. 3;

Figure 11 is the circuit diagram of the first stage drive circuit of Fig. 3;

Figure 12 is the circuit diagram of the final stage comparison circuit of Fig. 3;

Figure 13 is the circuit diagram of the final stage State-output circuit of Fig. 3;

Figure 14 is the circuit diagram of the final driving circuit of Fig. 3.

Embodiment

Below, by reference to the accompanying drawings and embodiment, the present invention is described further.

Embodiment mono-

As shown in Figure 1, a kind of balanced protection circuit of lithium battery, the quantity of described lithium battery is at least two, and all lithium batteries are connected in series.Described balanced protection circuit comprises: all and sample circuit, balancing circuitry, under-voltage protecting circuit, comparison circuit and the drive circuit, one first reference voltage, one second reference voltage, a supply voltage and the State-output circuit that with described lithium battery connect one to one identical with the quantity of described lithium battery.

Described sample circuit (can with reference to figure 4), for obtaining the sampling cell voltage of corresponding lithium battery, half of the virtual voltage that described sampling cell voltage can be lithium battery.Because the normal voltage scope of lithium battery is 3-4.2V, therefore, the first reference voltage is 1.5V, and the second reference voltage is 2.1V.The first reference voltage and the second reference voltage can be come by voltage conversion circuit transformation by supply voltage.

Described under-voltage protecting circuit (can with reference to figure 5); for judging whether the sampling cell voltage of corresponding lithium battery is greater than described the first reference voltage; if; disconnect with corresponding balancing circuitry; so that balancing circuitry is not subject to the control of under-voltage protecting circuit; if not, positive pole and the negative pole of controlling the lithium battery in corresponding balancing circuitry disconnect, so that balancing circuitry stops discharge process to lithium battery.

Described comparison circuit (can with reference to figure 7 or Figure 12), for the first reference voltage and the second reference voltage are compared with the sampling cell voltage of corresponding lithium battery respectively, and exports one first level signal.For example, if sample cell voltage between the first reference voltage and the second reference voltage, the first level signal is low level signal, otherwise is high level signal.

Described State-output circuit (can with reference to Figure 13), for according to the first level signal of all comparison circuits outputs, output one second electrical level signal.For example, if the first all level signals is low level signal, second electrical level signal is also low level signal, if wherein there is one first level signal, is high level signal, and second electrical level signal is high level signal.

Described drive circuit (can with reference to Figure 14), for according to second electrical level signal and the first corresponding level signal, judges whether to corresponding balancing circuitry output drive signal.For example, second electrical level signal is low level signal, the first level signal corresponding to explanation is also low level signal, drive circuit is output drive signal not, if second electrical level signal is high level signal, and the first corresponding level signal is high level signal, drive circuit output drive signal is to the balancing circuitry of connection corresponding to it.

Described balancing circuitry (can with reference to figure 6); be used for according to corresponding driving signal; the positive pole of controlling corresponding lithium battery is connected with negative pole; so that corresponding lithium battery is carried out to discharge process, until determining the sampling cell voltage of corresponding lithium battery, under-voltage protecting circuit is less than or equal to described the first reference voltage.

Described supply voltage, is used to sample circuit, under-voltage protecting circuit, comparison circuit and State-output circuit that operating voltage is provided.Supply voltage can be provided by DC power supply, also can be by civil power through direct current transformation circuit conversion, or provided by power-supply battery.

Embodiment bis-

In conjunction with shown in Fig. 2 to Figure 14, the balanced protection circuit of another kind of lithium battery, the present embodiment be take two lithium batteries and two-stage and is controlled comparison circuit and describe as example.Two lithium batteries are connected in series.Described balanced protection circuit comprises: two sample circuits, two balancing circuitrys, two under-voltage protecting circuits, a primary control comparison circuit, final stages are controlled comparison circuit, a reference voltage output circuit and a supply voltage VCC.

Because the primary control comparison circuit of the present embodiment only has one, institute thinks the 1st grade of control comparison circuit.The 1st grade of control comparison circuit comprises elementary comparison circuit, elementary the first State-output circuit, elementary the second State-output circuit, primary control circuit and first stage drive circuit.The 1st grade of control comparison circuit provides operating voltage by described supply voltage.

Final stage is controlled comparison circuit and is comprised final stage comparison circuit, final stage State-output circuit and final driving circuit.

The quantity of elementary comparison circuit, first stage drive circuit, final stage comparison circuit and final driving circuit is all identical with the quantity of lithium battery and connect one to one with lithium battery respectively.

Described reference voltage output circuit, for exporting 3 reference voltages, 3 reference voltages are designated as respectively the 1st reference voltage, the 2nd reference voltage, the 3rd reference voltage.The 1st reference voltage < the 2nd reference voltage < the 3rd reference voltage.Because the normal voltage scope of lithium battery is 3-4.2V, therefore, the 1st reference voltage is 1.5V, and the 2nd reference voltage is 1.8V, and the 3rd reference voltage is 2.1V.The 1st reference voltage, the 2nd reference voltage and the 3rd reference voltage all can be come by voltage conversion circuit transformation by supply voltage VCC.

As shown in Figure 4, described sample circuit, for obtaining the sampling cell voltage of corresponding lithium battery.Because the quantity of sample circuit is 2, be designated as respectively the 1st sample circuit and the 2nd sample circuit.The 1st sample circuit is comprised of resistance R 1, resistance R 12 to R14, differential amplifier U1.The 2nd sample circuit is comprised of resistance R 3 to R7, differential amplifier U11.Concrete annexation describes with the 2nd sample circuit, the inverting input of differential amplifier U11 connects with the negative pole B1 of corresponding lithium battery by resistance R 3, the normal phase input end of differential amplifier U11 connects with the anodal B2 of corresponding lithium battery by resistance R 4, the normal phase input end of differential amplifier U11 is also by resistance R 6 ground connection, the inverting input of differential amplifier U11 is also by resistance R 7 ground connection, the inverting input of differential amplifier U11 is also connected with the output of differential amplifier U11 by resistance R 5, the output of differential amplifier U11 is exported the sampling cell voltage BATV2 of corresponding lithium battery.Differential amplifier U11 and differential amplifier U1 all have supply voltage VCC power supply.The syndeton of the syndeton of the 1st sample circuit and the 2nd sample circuit is similar, difference is only that the inverting input of the differential amplifier U1 of the 1st sample circuit passes through the direct ground connection of resistance R 12, therefore, can omit an earth resistance of an inverting input, this is due to terminal B1, to connect the positive pole of corresponding lithium battery, and the direct ground connection of the negative pole of this lithium battery.Half of the virtual voltage that sampling cell voltage is lithium battery.

As shown in Figure 5, described under-voltage protecting circuit, for judging whether the sampling cell voltage of corresponding lithium battery is greater than described the 1st reference voltage; if; disconnect with corresponding balancing circuitry, if not, positive pole and the negative pole of controlling the lithium battery in corresponding balancing circuitry disconnect.Because the quantity of under-voltage protecting circuit is 2, be designated as respectively the 1st under-voltage protecting circuit and the 2nd under-voltage protecting circuit.The 1st under-voltage protecting circuit is comprised of resistance R 109 to R112, triode Q13 and operational amplifier U29.The 2nd under-voltage protecting circuit is comprised of resistance R 113 to R116, triode Q15 and operational amplifier U30.The 1st under-voltage protecting circuit of take carries out the explanation of syndeton as example; the inverting input of operational amplifier U29 connects with the sampling cell voltage BATV1 of corresponding lithium battery by resistance R 109; the normal phase input end of operational amplifier U29 is connected with the 1st reference voltage by resistance R 110; the output of operational amplifier U29 is connected with the base stage of triode Q13 by resistance R 111; the output of operational amplifier U29 is also by resistance R 112 ground connection; the grounded emitter of triode Q13, the collector electrode of triode Q13 connects with the control end DISC_01 of corresponding balancing circuitry.

In conjunction with shown in Fig. 7 to Figure 11, described the 1st grade of control comparison circuit, for by its elementary comparison circuit, the 1st reference voltage and the 2nd reference voltage being compared with the sampling cell voltage of corresponding lithium battery respectively, and exports one the 11st elementary level signal; By its elementary first State-output circuit, according to all the 11st elementary level signals, export one the 12nd elementary level signals; By its elementary second State-output circuit, according to all the 11st elementary level signals, export one the 13rd elementary level signals; By its primary control circuit, according to the 12nd elementary level signal and the 13rd elementary level signal, judge whether first stage drive circuit output the 11st elementary driving signal to correspondence, and judge whether that to final stage, controlling comparison circuit provides operating voltage; By its first stage drive circuit, according to the 11st elementary driving signal and the 11st elementary level signal, judge whether to corresponding balancing circuitry output the 12nd elementary driving signal.

As shown in Figure 7, the quantity of elementary comparison circuit is 2, is designated as respectively the 1st elementary comparison circuit and the 2nd elementary comparison circuit.The 1st elementary comparison circuit is comprised of resistance R 166 to R167, voltage comparator U43-A, voltage comparator U43-B, diode D2 and diode D3.The 2nd elementary comparison circuit is comprised of resistance R 2, resistance R 161 to R163, voltage comparator U42-A, voltage comparator U42-B, diode D4 and diode D5.The 1st elementary comparison circuit of take carries out annexation explanation as example, the normal phase input end of voltage comparator U43-B is connected with the 1st reference voltage by resistance R 164, the inverting input of voltage comparator U43-B is connected with sampling cell voltage BATV1 by resistance R 166, the inverting input of voltage comparator U43-A is connected with the 2nd reference voltage by resistance R 167, the normal phase input end of voltage comparator U43-A is connected with described sampling cell voltage BATV1 by resistance R 165, the anodic bonding of the output of voltage comparator U43-B and diode D2, the corresponding input (DRIVE1) of the negative electrode of diode D2 and elementary the first State-output circuit, the corresponding first input end (DRIVE1) of first stage drive circuit and the corresponding input (DRIVE1) of elementary the second State-output circuit connect, the anodic bonding of the output of voltage comparator U43-1 and diode D3, the negative electrode of diode D3 is connected with the negative electrode of diode D2.

As shown in Figure 8, described elementary the first State-output circuit comprises 2 the first State-output electronic circuits, is designated as respectively the 1st electronic circuit and the 2nd electronic circuit.The 1st electronic circuit is comprised of resistance R 671, resistance R 672 and triode Q113, and the 2nd electronic circuit is comprised of resistance R 674, resistance R 675 and triode Q114.The 1st electronic circuit of take carries out syndeton explanation as example, the base stage of triode Q113 is output (DRIVE1) connection with corresponding elementary comparison circuit by resistance R 672, the base stage of triode Q113 is also connected with described supply voltage VCC by resistance R 671, the grounded collector of triode Q113, the emitter of triode Q113 is connected with the first input end (STATE00) of primary control circuit.The 1st electronic circuit is only that with the difference of the 2nd electronic circuit the emitter of the triode Q113 of the 1st electronic circuit is also connected with described supply voltage VCC by a resistance R 673.

As shown in Figure 9, described elementary the second State-output circuit comprises diode D162, diode D163, resistance R 376, resistance R 377, triode Q29, resistance R 390, resistance R 389 and resistance R 713.Diode D162 connects with resistance R 376 and forms one first series arm, one end of the first series arm connects with the output (DRIVE1) of corresponding elementary comparison circuit, the other end of the first series arm is connected with the base stage of triode Q29, diode D163 connects with resistance R 377 and forms one second series arm, one end of the second series arm connects with the output (DRIVE2) of corresponding elementary comparison circuit, the other end of the second series arm is connected with the base stage of triode Q29, the base stage of triode Q29 is by resistance R 390 ground connection, the emitter of triode Q29 is by resistance R 713 ground connection, the emitter of triode Q29 is connected with second input (STATE01) of primary control circuit, the collector electrode of triode Q29 is connected with described supply voltage VCC by resistance R 389.

As shown in figure 10, the syndeton of described primary control circuit is: comprise that one is converted to the reduction voltage circuit of a comparison voltage by supply voltage VCC, described contrast potential is 1/3 of supply voltage VCC, described reduction voltage circuit comprises resistance R 711 and resistance R 712, supply voltage VCC is successively by resistance R 711 and resistance R 712 ground connection, and the connected node of resistance R 711 and resistance R 712 is used for exporting described comparison voltage.The inverting input of voltage comparator U100 is connected with described contrast potential by resistance R 445, the normal phase input end of voltage comparator U100 is connected with one end of resistance R 446, the other end of resistance R 446 is as second input (STATE01) of primary control circuit at the corresponding levels, the inverting input of voltage comparator U115 is connected with one end of resistance R 437, the other end of resistance R 437 is as the first input end (STATE00) of primary control circuit at the corresponding levels, the normal phase input end of voltage comparator U115 by resistance R 618 with compare voltage and be connected, the output of voltage comparator U100 is connected with the base stage of triode Q37 by resistance R 449, the base stage of triode Q37 is by resistance R 448 ground connection, the grounded emitter of triode Q37, the emitter of triode Q37 is the second input (CHANNEL0) connection with corresponding first stage drive circuit by capacitor C 11, the collector electrode of triode Q37 is connected with the grid of metal-oxide-semiconductor Q35, the collector electrode of triode Q37 is connected with the drain electrode of metal-oxide-semiconductor Q35 by resistance R 444, second input (CHANNEL0) of the source electrode of metal-oxide-semiconductor Q35 and corresponding first stage drive circuit, the base stage of the base stage of triode Q37 and triode Q98 is all connected with the output of voltage comparator U115 by resistance R 436, the base stage of triode Q98 is connected with the source electrode of metal-oxide-semiconductor Q33 by resistance R 716, the grounded collector of triode Q98 and being connected with the source electrode of metal-oxide-semiconductor Q27 by capacitor C 12, the source electrode of metal-oxide-semiconductor Q27 is used to final stage to control comparison circuit operating voltage (POWER00) is provided, the emitter of triode Q98 is connected with the drain electrode of metal-oxide-semiconductor Q27 by resistance R 714, the emitter of triode Q98 is connected with the grid of metal-oxide-semiconductor Q27, the drain electrode of the drain electrode of metal-oxide-semiconductor Q35 and metal-oxide-semiconductor Q27 is all connected with the source electrode of metal-oxide-semiconductor Q33, the drain electrode of metal-oxide-semiconductor Q33 is connected with described supply voltage VCC, the first input end of primary control circuit at the corresponding levels successively logical diode D197 is connected with the base stage of triode Q80 with resistance R 577, the first input end of primary control circuit at the corresponding levels is connected with the base stage of triode Q80 with resistance R 578 by diode D198 successively, the base stage of triode Q80 is by resistance R 435 ground connection, the grounded emitter of triode Q80 and being connected with the source electrode of metal-oxide-semiconductor Q33 by capacitor C 17, the collector electrode of triode Q80 is connected with the grid of metal-oxide-semiconductor Q33, the collector electrode of triode Q80 is connected with described supply voltage VCC by resistance R 434.

As shown in figure 11, described just stage drive circuit is 2, is designated as respectively just stage drive circuit of the 1st first stage drive circuit and the 2nd.The 1st first stage drive circuit is comprised of resistance R 442, resistance R 443, resistance R 698, resistance R 715, resistance R 447, diode D214 and triode Q36.The 2nd first stage drive circuit is comprised of resistance R 456, resistance R 457, resistance R 699, resistance R 717, resistance R 458, diode D215 and triode Q40.Take the 1st just stage drive circuit carry out syndeton explanation as example, the collector electrode of triode Q36 is connected with one end of resistance R 442, the other end of resistance R 442 is as second input (CHANNEL0) of the 1st first stage drive circuit, the base stage of triode Q36 is connected with the negative electrode of diode D214 by resistance 698, the anode of D diode 214 is as the first input end (DRIVE1) of the 1st first stage drive circuit, the base stage of triode Q36 is by resistance R 443 ground connection, the anode of diode D214 is by resistance R 715 ground connection, the emitter of triode Q35 is by resistance R 447 ground connection, the emitter of triode Q36 connects with the control end (DISC_01) of corresponding balancing circuitry.

In conjunction with shown in Figure 12 to Figure 14, described final stage is controlled comparison circuit, for by its final stage comparison circuit, the 3rd reference voltage and the 2nd reference voltage being compared with the sampling cell voltage of corresponding lithium battery respectively, and exports one first final stage level signal; By its final stage State-output circuit, according to all the first final stage level signals, export one second final stage level signals; By its final driving circuit, according to the second final stage level signal and the first corresponding final stage level signal, judge whether to drive signal to corresponding balancing circuitry output final stage.

As shown in figure 12, described final stage comparison circuit is 2, is designated as respectively the 1st final stage comparison circuit and the 2nd final stage comparison circuit.The 1st final stage comparison circuit is comprised of resistance R 324 to R327, voltage comparator U85-A, voltage comparator U85-B, diode D80 and diode D81, and the 2nd final stage comparison circuit is comprised of resistance R 328 to R331, voltage comparator U86-A, voltage comparator U86-B, diode D82 and diode D83.The 1st final stage comparison circuit of take carries out syndeton explanation as example, the normal phase input end of voltage comparator U85-B is connected with the 2nd reference voltage by resistance R 324, the inverting input of voltage comparator U85-B is connected with described sampling cell voltage by resistance R 326, the inverting input of voltage comparator U85-A is connected with the 3rd reference voltage by resistance R 327, the normal phase input end of voltage comparator U85-A is connected with described sampling cell voltage by resistance R 325, the anodic bonding of the output of voltage comparator U85-B and diode D80, the first input end (DRIVE31) of the corresponding input (DRIVE31) of the negative electrode of diode D80 and final stage State-output circuit and corresponding final driving circuit connects, the anodic bonding of the output of voltage comparator U85-A and diode D81, the negative electrode of diode D81 is connected with the negative electrode of diode D80.

As shown in figure 13, described final stage State-output circuit comprises diode D148, resistance R 421, diode D149, resistance R 422, resistance R 590, resistance R 589, metal-oxide-semiconductor 85, capacitor C 19 and triode Q86.Diode D148 connects with resistance R 421 and forms one the 3rd series arm, one end of the 3rd series arm connects with the output (DRIVE31) of corresponding final stage comparison circuit, the other end of the 3rd series arm is connected with the base stage of triode Q86, diode D149 connects with resistance R 422 and forms one the 4th series arm, one end of the 4th series arm connects with the output (DRIVE32) of corresponding final stage comparison circuit, the other end of the 4th series arm is connected with the base stage of triode Q86, the base stage of triode Q86 is by resistance R 590 ground connection, the grounded emitter of triode Q86 and being connected with the source electrode of metal-oxide-semiconductor Q85 by capacitor C 19, the source electrode of metal-oxide-semiconductor Q85 is connected with second input (CHANNEL03) of final driving circuit, the collector electrode of triode Q86 is connected with described supply voltage VCC and is connected with the drain electrode of metal-oxide-semiconductor Q85 by resistance R 589, the collector electrode of triode Q86 is connected with the grid of metal-oxide-semiconductor Q85.

As shown in figure 14, described final driving circuit is 2, is designated as respectively the 1st final driving circuit and the 2nd final driving circuit.The 1st final driving circuit is comprised of resistance R 574, resistance R 575, resistance R 576, resistance R 616, resistance R 889, diode D161 and triode Q34, and the 2nd final driving circuit is comprised of resistance R 580, resistance R 582, resistance R 581, resistance R 617, resistance R 890, diode D185 and triode Q82.The 1st final driving circuit of take is carried out syndeton explanation as example, the collector electrode of triode Q34 is connected with one end of resistance R 574, the other end of resistance R 574 is as second input (CHANNEL03) of the 1st final driving circuit, the base stage of triode Q34 is connected with the negative electrode of diode D161 by resistance R 616, the anode of diode D161 is as the first input end (DRIVE31) of the 1st final driving circuit, the base stage of triode Q34 is by resistance R 575 ground connection, the anode of diode D161 is by resistance R 889 ground connection, the emitter of triode Q34 is by resistance R 576 ground connection, the emitter of triode Q34 connects with the control end (DISC_01) of corresponding balancing circuitry.

As shown in Figure 6, described balancing circuitry, for driving signal according to the 12nd of correspondence the elementary driving signal or final stage, the positive pole of controlling corresponding lithium battery is connected by power discharge resistance with negative pole, so that corresponding lithium battery is carried out to discharge process.Described balancing circuitry is 2, is designated as respectively the 1st balancing circuitry and the 2nd balancing circuitry.The 1st balancing circuitry is comprised of photoelectrical coupler U9, resistance R 82 (being power discharge resistance), resistance R 48, resistance R 46 and metal-oxide-semiconductor Q6, and the 2nd balancing circuitry is comprised of photoelectrical coupler U8, resistance R 81 (being another power discharge resistance), resistance R 45, resistance R 43 and metal-oxide-semiconductor Q5.The 1st balancing circuitry of take carries out syndeton explanation as example, the drain electrode of metal-oxide-semiconductor Q6 connects with the anodal B1 of corresponding lithium battery by resistance R 82, the source electrode of metal-oxide-semiconductor Q6 connects with the negative pole B-of corresponding lithium battery, the transistor emitter output of photoelectrical coupler U9 is connected with the grid of metal-oxide-semiconductor Q6, the transistor emitter output of photoelectrical coupler U9 also connects with the negative pole B-of corresponding lithium battery by resistance R 46, the transistor collector input of photoelectrical coupler U9 connects with the anodal B1 of corresponding lithium battery by resistance R 48, the diode input of photoelectrical coupler U9 is all connected with the output (DISC_01) of the output (DISC_01) of corresponding under-voltage protecting circuit and corresponding drive circuit.

Described supply voltage VCC, is used to sample circuit and under-voltage protecting circuit that operating voltage is provided.

The operation principle of the present embodiment is as follows:

It is 1.5V that the 1st reference voltage is set, and the 2nd reference voltage is 1.8V, and the 3rd reference voltage is 2.1V.User also can add the quantity of reference voltage and arrange as required, as 1.5V, and 1.65V, 1.8V, 1.95V, 2.1V, reference voltage is more, and precision is higher.

Lithium battery was ganged up row's pin and was connected with sample circuit, output BATV (cell voltage of sampling) for the voltage of single lithium battery half.

In under-voltage protecting circuit; by BATV and 1.5V comparison; if BATV>1.5V; triode Q13 cut-off, under-voltage protecting circuit and balancing circuitry disconnect, and do not process; if BATV≤1.5V;, by the control end ground connection of balancing circuitry, while making single lithium battery voltage lower than 3.0V, do not process, thereby protection lithium battery can over-discharge can.

When BATV>1.5V, single lithium battery voltage is processed according to the method for successively approaching, specific as follows described in:

First, determine the condition that balancing circuitry starts, the condition triggering is exactly that monomer lithium electricity battery pressure reduction exceeds higher limit, higher limit is chosen according to reference voltage value and is determined, as the 1st reference voltage, select 1.5V, the 2nd reference voltage is selected 1.8V, illustrates that cell voltage do not process between 3.0-3.6V, but outside this voltage range, single lithium battery voltage difference will be carried out discharge process higher than the lithium battery of 0.6V.The present embodiment has 1 primary control comparison circuit and 1 final stage to control comparison circuit, from integral body, is that secondary comparison is processed, and the order of startup is according to the conditional decision of power supply. specific as follows:

A. due to power supply order, first (principle of elementary comparison circuit is that lithium battery is pressed between 1.5-1.8V to start the 1st grade of control comparison circuit, DRIVEn low level output, otherwise high level output, n=1,2), can analyze the sampling cell voltage BATVn of single lithium battery whether between 1.5-1.8V (3.0-3.6V), if, elementary comparison circuit output DRIVEn low level, otherwise DRIVEn exports high level, having 3 kinds of situation: situation 1:DRIVEn is here high level (sampling cell voltage is all higher than 1.8V) entirely; Situation 2:DRIVEn is low level (sampling cell voltage is between 1.5-1.8V) entirely; Situation 3:DRIVEn entirely for low and high level, have (sampling cell voltage have between 1.5-1.8V, also have higher than 1.8V's).

B. elementary the first State-output circuit, it is whether the sampling cell voltage that gathers single lithium battery has between 1.5-1.8V, if single lithium battery has 1 at least within the scope of this (DRIVEn has 1 at least and is output as low level), STATE00 just can draw ground, output low level; Elementary the second State-output circuit, sampling cell voltage has 1 at least higher than 1.8V (DRIVEn has 1 at least and is output as high level), STATE01 just can export high level, by elementary the first State-output circuit and elementary the second State-output circuit, can obtain 3 kinds of combinations, combination 1 (STATE00:STATE01=00, the sampling cell voltage of single lithium battery is between 1.5-1.8V); Combination 2 (STATE00:STATE01=01, existing also the having higher than 1.8V's between 1.5-1.8V of sampling cell voltage of single lithium battery); Combination 3 (STATE00:STATE01=11, the sampling cell voltage of single lithium battery is entirely on 1.8V);

C. 3 kinds of possible composite signals, be input in primary control circuit, if the situation of combination 1, whole circuit will not done Balance Treatment and (close metal-oxide-semiconductor Q33, metal-oxide-semiconductor Q35, CHANNEL0 no-output), do not give final stage control ratio compared with circuit supply (closing metal-oxide-semiconductor Q27, POWER00 no-output) simultaneously, make its inefficacy yet.If the situation of combination 2: close final stage control ratio compared with circuit supply (closing metal-oxide-semiconductor Q27, POWER00 no-output), open elementary drive circuitry (opening metal-oxide-semiconductor Q33, metal-oxide-semiconductor Q35, CHANNEL0 output drive signal).If the situation of combination 3: open final stage control ratio compared with circuit supply (opening metal-oxide-semiconductor Q27, POWER00 output), close elementary drive circuitry (closing metal-oxide-semiconductor Q33, metal-oxide-semiconductor Q35, CHANNEL0 output).

The principle that final stage is controlled comparison circuit and the 1st grade of control comparison circuit is similar, just a reference source voltage range is different, final stage is the higher limit of reference voltage, be equivalent to cancel elementary the first State-output circuit and primary control circuit, because battery voltage limit value is 4.2V, it directly can judge the cell voltage that whether has the single lithium battery that exceeds 4.2V in final stage comparison circuit, thereby open balancing circuitry, final stage State-output circuit provides final driving circuit supply power voltage, and final driving circuit just can drive corresponding balancing circuitry to discharge to corresponding single lithium battery in conjunction with final stage comparison circuit.

Balancing circuitry adopts photoelectric coupler isolation to control, and prevents control and safety problem that the pressure reduction problem between lithium battery string (high voltage) and control circuit (low-voltage) causes.

From above-mentioned two embodiment, embodiment mono-only has one-level to control comparison circuit and 2 reference voltages, and precision is lower, and embodiment bis-has secondary to control comparison circuit and 3 reference voltages, and precision is compared with embodiment mono-height.Therefore, if it is more to control the progression of comparison circuit, reference voltage is more, and precision is just higher.

Cost of manufacture of the present invention is low, use simple, can arbitrarily combine, the artificial voltage difference standard that single lithium battery is set, in charging, electric discharge, standing 3 kinds of situations, real-time ensuring lithium battery balance coupling, has improved the useful life of multi-series lithium battery, has increased stability and the reliability of multi-series lithium battery.

For a person skilled in the art, can make other various corresponding changes and distortion according to technical scheme described above and design, and these all changes and distortion all should belong to the protection range of the claims in the present invention within.

Claims

1. the balanced protection circuit of lithium battery, the quantity of described lithium battery is at least two, and all lithium batteries are connected in series, it is characterized in that, described balanced protection circuit comprises: all and sample circuit, balancing circuitry, under-voltage protecting circuit, comparison circuit and the drive circuit, one first reference voltage, one second reference voltage, a supply voltage and the State-output circuit that with described lithium battery connect one to one identical with the quantity of described lithium battery;

2. the balanced protection circuit of lithium battery, the quantity of described lithium battery is at least two, and all lithium batteries are connected in series, it is characterized in that, described balanced protection circuit comprises: all identical with the quantity of described lithium battery and control comparison circuit, a reference voltage output circuit and a supply voltage with sample circuit, balancing circuitry and under-voltage protecting circuit, at least one primary control comparison circuit, a final stage that described lithium battery connects one to one;

……；

3. balanced protection circuit as claimed in claim 2, it is characterized in that, described sample circuit comprises the first to the 5th resistance and differential amplifier, the inverting input of differential amplifier connects with the negative pole of corresponding lithium battery by the 3rd resistance, the normal phase input end of differential amplifier connects with the positive pole of corresponding lithium battery by the 4th resistance, the normal phase input end of differential amplifier is also by the 5th grounding through resistance, the inverting input of differential amplifier is also by the first grounding through resistance, the inverting input of differential amplifier is also connected with the output of differential amplifier by the second resistance, the output of differential amplifier is exported the sampling cell voltage of corresponding lithium battery.

4. balanced protection circuit as claimed in claim 2, it is characterized in that, described under-voltage protecting circuit comprises the 6th to the 9th resistance, operational amplifier and the first triode, the inverting input of operational amplifier connects with the sampling cell voltage of corresponding lithium battery by the 6th resistance, the normal phase input end of operational amplifier is connected with the 1st reference voltage by the 7th resistance, the output of operational amplifier is connected with the base stage of the first triode by the 8th resistance, the output of operational amplifier is also by the 9th grounding through resistance, the grounded emitter of the first triode, the collector electrode of the first triode is connected with the control end of balancing circuitry.

5. balanced protection circuit as claimed in claim 2, it is characterized in that, described balancing circuitry comprises photoelectrical coupler, the the tenth to the 12 resistance and the first metal-oxide-semiconductor, the drain electrode of the first metal-oxide-semiconductor connects with the positive pole of corresponding lithium battery by the 11 resistance, the source electrode of the first metal-oxide-semiconductor connects with the negative pole of corresponding lithium battery, the transistor emitter output of photoelectrical coupler is connected with the grid of the first metal-oxide-semiconductor, the transistor emitter output of photoelectrical coupler also connects with the negative pole of corresponding lithium battery by the 12 resistance, the transistor collector input of photoelectrical coupler connects with the positive pole of corresponding lithium battery by the 11 resistance, the diode input of photoelectrical coupler is all connected with the output of the output of corresponding under-voltage protecting circuit and corresponding drive circuit.

6. balanced protection circuit as claimed in claim 2, it is characterized in that, described elementary comparison circuit comprises the 13 to the 16 resistance, the first voltage comparator, second voltage comparator, the first diode and the second diode, the normal phase input end of the first voltage comparator is connected with N reference voltage by the 14 resistance, the inverting input of the first voltage comparator is connected with described sampling cell voltage by the 13 resistance, the inverting input of second voltage comparator is connected with N+1 reference voltage by the 16 resistance, the normal phase input end of second voltage comparator is connected with described sampling cell voltage by the 15 resistance, the anodic bonding of the output of the first voltage comparator and the first diode, the corresponding input of the negative electrode of the first diode and elementary the first State-output circuit, the corresponding input of the first input end of corresponding first stage drive circuit and elementary the second State-output circuit connects, the anodic bonding of the output of second voltage comparator and the second diode, the negative electrode of the second diode is connected with the negative electrode of the first diode.

7. balanced protection circuit as claimed in claim 6, it is characterized in that, described elementary the first State-output circuit comprises the first State-output electronic circuit identical with the quantity of lithium battery, each first State-output electronic circuit comprises the 17 resistance, the 18 resistance and the second triode, the base stage of the second triode connects with the output of corresponding elementary comparison circuit by the 18 resistance, the base stage of the second triode is also connected with described supply voltage by the 17 resistance, the grounded collector of the second triode, the emitter of the second triode is connected with the first input end of primary control circuit, the emitter of the second triode of one of them the first State-output electronic circuit is also connected with described supply voltage by 1 the 19 resistance,

8. balanced protection circuit as claimed in claim 2, it is characterized in that, described final stage comparison circuit comprises the 43 to the 46 resistance, the 5th voltage comparator, the 6th voltage comparator, the 7th diode and the 8th diode, the normal phase input end of the 5th voltage comparator is connected with N+1 reference voltage by the 44 resistance, the inverting input of the 5th voltage comparator is connected with described sampling cell voltage by the 43 resistance, the inverting input of the 6th voltage comparator is connected with N+2 reference voltage by the 46 resistance, the normal phase input end of the 6th voltage comparator is connected with described sampling cell voltage by the 45 resistance, the anodic bonding of the output of the 5th voltage comparator and the 7th diode, the first input end of the corresponding input of the negative electrode of the 7th diode and final stage State-output circuit and corresponding final driving circuit connects, the anodic bonding of the output of the 6th voltage comparator and the 8th diode, the negative electrode of the 8th diode is connected with the negative electrode of the 7th diode.

9. balanced protection circuit as claimed in claim 8, it is characterized in that, described final stage State-output circuit comprises nine diode and four ten three resistance identical with the quantity of lithium battery, the 8th triode and the 44 to the 45 resistance, each the 9th diode forms a series arm with one the 43 corresponding resistance series connection, one end of each series arm connects with the output of corresponding final stage comparison circuit, the other end of each series arm is connected with the base stage of the 8th triode, the base stage of the 8th triode is by the 45 grounding through resistance, the grounded emitter of the 8th triode and being connected with the source electrode of the 5th metal-oxide-semiconductor by the 4th electric capacity, the source electrode of the 5th metal-oxide-semiconductor is connected with the second input of final driving circuit, the collector electrode of the 8th triode is connected with described supply voltage by the 44 resistance and is connected with the drain electrode of described the 5th metal-oxide-semiconductor, the collector electrode of the 8th triode is connected with the grid of the 5th metal-oxide-semiconductor,