CN2909661Y

CN2909661Y - Battery charging balance circuit

Info

Publication number: CN2909661Y
Application number: CN 200620059512
Authority: CN
Inventors: 周海
Original assignee: Individual
Current assignee: Individual
Priority date: 2006-05-22
Filing date: 2006-05-22
Publication date: 2007-06-06
Anticipated expiration: 2016-05-22

Abstract

A battery charging balanced circuit, including a shunt element and a switch module. The switch module consists of a voltage setting circuit parallel to external rechargeable batteries, and a switch circuit comprising at least two connected three-terminal switch tube, the last one among which is a field effect transistor. The switch end of the field effect transistor is connected to the external rechargeable batteries in parallel after connecting to the shunt element in series, and the controlling end of the field effect transistor is connected to a switch end of the upper three-terminal switch tube whose another switch end is connected to the circuit to form a loop. The controlling end of the first three-terminal switch tube is connected to the voltage setting circuit as the controlling end of the switch circuit. The utility model parallel to one of the battery of the battery set overcomes the problem of overcharging by activating the switch module when the limit voltage of the battery is reached and shunting the currents by the shunt element. Adjacent batteries can charge normally after shunting, yet providing low current to the battery in circuit. The charging balance of the battery set is attained after a number of adjustments.

Description

The battery charge balancing circuitry

Technical field

The utility model relates to the ancillary technique that charges the battery, and particularly relates to a kind of charge balancing circuit that is used for series battery.

Background technology

In the middle of the polyphone battery pack, because production technology all exists bigger difference at aspects such as capacity, internal resistances.If the capacity of certain single battery or internal resistance are too high when charging normal, the voltage of this batteries (problem battery) just the overtension phenomenon will inevitably occur so, thereby arrive deboost (weighing apparatus is pressed) in advance than adjacent cell, if do not limited this moment, voltage will continue to rise.Overtension can produce corresponding different damage to dissimilar rechargeable batteries.As, to lead-acid battery, overtension will cause a large amount of gassings of battery and dehydration (electrolyte solution loss).Through going round and beginning again, the vicious circle charging will appear in the problem battery, thereby because of dehydration too much causes damaging in advance, cause adjacent cell also because of overcharging phenomenons such as causing thermal runaway, dehydration then, make it thorough damage.

Summary of the invention

The purpose of this utility model is exactly in order to overcome the above problems, provide a kind of when being used for preventing series battery charge fast single battery overcharge or owe to fill, suppresses the battery charge balancing circuitry that the vicious circle of problem battery is charged.

For achieving the above object, the utility model has adopted following technical scheme: a kind of battery charge balancing circuitry, be to be used for the diverter branch in parallel with rechargeable battery, comprise vent diverter and switch module, described switch module comprises voltage setting circuit and switching circuit, described voltage setting circuit external charge battery in parallel, described switching circuit comprises the three terminal switching tubes that two utmost points connect at least, wherein last three terminal switching tube is field effect transistor, the switch terminals of the described field effect transistor external charge battery in parallel behind the described vent diverter of connecting, a switch terminals of the control termination previous stage three terminal switching tubes of described field effect transistor, another switch terminals then constitutes the loop in the place in circuit; First three terminals control end of switching tube inserts in the voltage setting circuit as the control end of switching circuit, and when the voltage setting circuit both end voltage surpassed its set point, described control end was controlled described switch terminals and connected.

Preferably, described voltage setting circuit comprises the voltage stabilizing didoe and the current-limiting resistance of series connection, and when voltage stabilizing didoe punctured, the electric current that flows into described control end increased with the rising of voltage.

Further preferably, described current-limiting resistance comprises at least one adjustable rheostat, makes the shunting magnitude of voltage of setting to adjust within the specific limits.

Vent diverter in the foregoing circuit preferably adopts ceramic power resistor.

Adopt such scheme, the utility model beneficial technical effects is: adopt field effect transistor can dwindle the Q2 hysteresis conduction problem of bringing triode Q1 amplification region, to reach the purpose of quick conducting, make Q2 be operated in accurate on off state, improve control precision.

The voltage stabilizing didoe that circuit of the present utility model has suitable puncture voltage by setting, in the time of can making voltage not reach this puncture voltage, not conducting of circuit, thus realize zero-power.

The ceramic power resistor that battery charge balancing circuitry of the present utility model passes through to use sheet is as shunt resistance, and the heating that has overcome the generation of employing plain cylindrical form resistance is concentrated, heat can't get rid of and cause plastic casing because of overheated problem of being out of shape.

Circuit of the present utility model is widely used in the charging balanced protection of all kinds of polyphone lead-acid battery groups, is specially adapted to the supporting use of lead-acid battery group, also is fit to the use of installing additional in maintenance market.Dispose the normal operating period that can prolong battery behind this circuit greatly.And circuit of the present utility model and balancer are simple in structure, and volume is little, the precision height, and cost is low, and is easy for installation.

Description of drawings

Also in conjunction with the accompanying drawings the utility model is described in further detail below by specific embodiment.

Fig. 1 is a kind of battery charge balancing circuitry figure of the present utility model.

Fig. 2 is the external structure schematic diagram of a kind of battery charge balancer of the present utility model.

Fig. 3 is the side structure schematic diagram of battery charge balancer reserve part shell among Fig. 2.

Embodiment

Embodiment one, a kind of battery charge balancing circuitry as shown in Figure 1, are to be used for the diverter branch in parallel with rechargeable battery.Described circuit comprises resistance R 4 and the switch module as vent diverter.Described switch module comprises the cascade switching circuit that is made of triode Q1 and field effect transistor Q2; The voltage setting circuit that constitutes by current-limiting resistance R1, R2, W1 and voltage stabilizing didoe AZ1 series connection; And capacitor C 1.Wherein resistance W1 is an adjustable slide rheostat.

The switch terminals of field effect transistor Q2 is as the switch terminals series resistance R4 of switching circuit, one termination anode plate grid of resistance R 3, the other end also connects the control utmost point of Q2 and the collection utmost point of Q1, the conducting of field effect transistor Q2 with whether in the place in circuit rechargeable battery is shunted by controlling resistance R4, the state of field effect transistor Q2 is by its higher level's switching tube Q1 control, and the control end of Q1 inserts in the voltage setting circuit as the control end of switching circuit.Here the purpose that adopts the two-stage switch controlled is in order to improve the accuracy of circuit control, also can only use a switching tube or a plurality of cascade switching tube to control in principle, but the single-stage control precision is not high enough, and progression too much can cause the circuit complexity, increase cost, and to not significantly effect of control precision.Here the Q2 hysteresis conduction problem that adopts field effect transistor to dwindle to bring triode Q1 amplification region to reach the purpose of quick conducting, makes Q2 be operated in accurate on off state, improves control precision.

Voltage setting circuit external charge battery in parallel is made of R2, the W1, AZ1 and the R1 that connect successively, and the control end of Q1 is connected between W1 and the AZ1.When charging voltage was higher than the reverse breakdown voltage of AZ1, AZ1 was open-minded, and the control end of Q1 promptly has electric current to flow through, and along with the Control current of the rising Q1 of shunt voltage constantly strengthens, when reaching certain intensity, Q1 is promptly open-minded.The relation of the rising of shunt voltage and Q1 base current is determined by the resistance of current-limiting resistance, therefore, can change the shunting magnitude of voltage of this battery charge balancing circuitry by adjustment slide rheostat W1.Certainly, if only need to determine unique shunting magnitude of voltage, also can replace slide rheostat W1 with conventional, electric-resistance.In addition, for fear of unexpected reverse current occurring, return diode D3 identical of AZ1 series connection with the shunt voltage direction.

In order to improve the stability of circuit, also increase is provided with a capacitor C 1 external charge battery in parallel.

During work, with the single battery in the rechargeable battery set of being parallel to of this circuit, the both positive and negative polarity of noting making battery is the negative positive pole of corresponding voltage stabilizing didoe respectively.When charging voltage is lower than the puncture voltage of voltage stabilizing didoe AZ1, this not conducting of balancing circuitry, thus realize zero-power.By adjusting the resistance of W1, field effect transistor Q2 begins conducting when making shunt voltage reach the deboost of rechargeable battery, thus electric current shunt by the R4 bypass, to reduce the charging current of this problem battery.The continuation of also giving with less electric current when shunting back adjacent cell charges normal is charged, and can realize the charging balance of battery pack after charging is adjusted for several times fully.

For better understanding the utility model, provide a kind of structure that can be used for the utility model circuit package below, promptly a kind of battery charge balancer as Fig. 2, shown in Figure 3, comprises housing and battery charge balancing circuitry.This battery charge balancing circuitry is the circuit described in the embodiment 1, its vent diverter 21 adopts the flaky pottery power resistor, and other elements in the circuit except that the sheet heating resistor all are installed on the circuit board 22, and the entire circuit structure is more compact like this, are convenient to encapsulation.

The battery charge balancing circuitry is used for the two poles of the earth in parallel with rechargeable battery and draws from encapsulating housing respectively; A sidewall of encapsulating housing is made of metal fin 11, and remainder is the plastic packaging shell.It is fixing that flaky pottery power resistor 21 is close to fin 11, to reach better heat radiating effect.Circuit board 22 is fixed in the encapsulating housing.Because metal fin 11 parts as housing own, one side is close to pellet resistance 21, and another side is exposed to the balancer outside, is beneficial to heat radiation.This balancer adopts plastic package process to make aluminium sheet, circuit module, sheet shunt resistance form an integral body, thus good heat dissipation effect, good looking appearance, easy for installation.

Claims

1, a kind of battery charge balancing circuitry, be to be used for the diverter branch in parallel with rechargeable battery, it is characterized in that: comprise vent diverter and switch module, described switch module comprises voltage setting circuit and switching circuit, described voltage setting circuit external charge battery in parallel, described switching circuit comprises the three terminal switching tubes that two utmost points connect at least, wherein last three terminal switching tube is field effect transistor, the switch terminals of the described field effect transistor external charge battery in parallel behind the described vent diverter of connecting, a switch terminals of the control termination previous stage three terminal switching tubes of described field effect transistor, another switch terminals then constitutes the loop in the place in circuit; First three terminals control end of switching tube inserts in the voltage setting circuit as the control end of switching circuit, and when the voltage setting circuit both end voltage surpassed its set point, described control end was controlled described switch terminals and connected.

2, battery charge balancing circuitry according to claim 1 is characterized in that: described voltage setting circuit comprises the voltage stabilizing didoe and the current-limiting resistance of series connection, and when voltage stabilizing didoe punctured, the electric current that flows into described control end increased with the rising of voltage.

3, battery charge balancing circuitry according to claim 2 is characterized in that: described current-limiting resistance comprises at least one adjustable rheostat.

4, according to any described a kind of battery charge balancing circuitry of claim 1-3, it is characterized in that: described vent diverter adopts ceramic power resistor.