A kind of lithium battery charging circuitTechnical field
The utility model belongs to technical field of lithium batteries, is specifically related to a kind of lithium battery charging circuit.
Background technology
Lithium ion battery is a kind of new energy mode developed in 20th century, compare Ni-MH battery in the past, lithium battery have voltage high, store and have extended cycle life, charged maintenance energy is strong, lowly pollute and the advantage such as larger operating temperature range arranged, be widely used in as in the mobile hand-held devices such as mobile phone, digital camera, POS machine, and exist as main form of power.
In the lithium battery use procedure, often need to use lithium battery charger to be charged to lithium battery, but lithium battery is there are certain requirements to peripheral protective circuit: lithium battery can not be used large current charge in the situation that voltage is very low, can shorten the useful life of battery; At cell voltage palpus constant voltage charge when protecting voltage, otherwise easily overcharge, require charging current to be adjusted according to the voltage of lithium battery.
But existing lithium battery charging circuit can not be adjusted charging current automatically according to the voltage of lithium battery, the excessive situation of charging current while easily the lithium battery low-voltage occurring, and the useful life of shortening battery, over-charge of lithium battery also may occur, cross the situation of putting, lithium battery is damaged, have the hidden danger of blast on fire.
The utility model content
For the existing above-mentioned deficiency of prior art, the purpose of this utility model is to provide a kind of lithium battery charging circuit that detects the charge parameters such as voltage, electric current, temperature can Real-time the time, charging process is carried out to Based Intelligent Control, improve charging security, shorten the charging interval of battery, extend the useful life of battery.
For achieving the above object, the utility model will be achieved through the following technical solutions: a kind of lithium battery charging circuit, comprise the charge power supply unit for electric power supply is provided and the lithium cell charging interface unit accessed for charged lithium cells, it is characterized in that: described lithium battery charging circuit also comprises the MCU control unit for the work of control circuit unit, be provided with temperature detecting unit between described lithium cell charging interface unit and MCU control unit, voltage detection unit and current detecting unit, be provided with the charging output control unit between described charge power supply unit and lithium cell charging interface unit, described MCU control unit also is connected with the charging output control unit.
Whole charging circuit is by MCU control unit controlling run, the MCU control unit is for the default charging current value corresponding with magnitude of voltage, in charging process, voltage detection unit and current detecting unit carry out continuous monitoring to lithium battery voltage and charging current respectively, temperature detecting unit is monitored the real time temperature of lithium battery, the real-time lithium battery parameter gathered according to each detecting unit, the MCU control unit sends control signal to the charging output control unit, and the charge parameter of lithium battery is adjusted.
By the real-time detection of the charge parameters such as the voltage to lithium battery, electric current, temperature, realize the Based Intelligent Control of charging process, improve charging security, shorten the charging interval of battery, extend the useful life of battery.
As preferably, described MCU control unit also is connected with the charged state indicating member.
The utility model has the following advantages and beneficial effect compared to existing technology:
The utility model arranges the charge parameters such as voltage that voltage detection unit, current detecting unit, temperature detecting unit detect lithium battery in real time, electric current, temperature, and by the MCU control unit, charging process is carried out to Based Intelligent Control, improve charging security, shorten the charging interval of battery, extend the useful life of battery.
The accompanying drawing explanation
The structured flowchart that Fig. 1 is a kind of lithium battery charging circuit of the utility model.
Embodiment
Below in conjunction with embodiment and accompanying drawing, the utility model is described in further detail, but execution mode of the present utility model is not limited to this.
Embodiment as shown in Figure 1, a kind of lithium battery charging circuit, comprise the charge power supply unit for electric power supply is provided and the lithium cell charging interface unit accessed for charged lithium cells, it is characterized in that: described lithium battery charging circuit also comprises the MCU control unit for the work of control circuit unit, be provided with temperature detecting unit between described lithium cell charging interface unit and MCU control unit, voltage detection unit and current detecting unit, be provided with the charging output control unit between described charge power supply unit and lithium cell charging interface unit, described MCU control unit also is connected with the charging output control unit.
As preferably, described MCU control unit also is connected with the charged state indicating member.
Whole charging circuit is by MCU control unit controlling run, the MCU control unit is for the default charging current value corresponding with magnitude of voltage, in charging process, voltage detection unit and current detecting unit carry out continuous monitoring to lithium battery voltage and charging current respectively, temperature detecting unit is monitored the real time temperature of lithium battery, the real-time lithium battery parameter gathered according to each detecting unit, the MCU control unit sends control signal to the charging output control unit, and the charge parameter of lithium battery is adjusted.
While charging normal, the precharge before this of charging, after voltage rises to threshold voltage, enter with current constant mode and carry out quick charge, when nearly 4.2 V of average monomer lithium battery crimping, enter in the constant voltage mode, charged expire the stage of filling, be finally the complete charge stage.Stages can be realized automatic conversion, and the precision of constant voltage charge voltage is scholar 0.8%, and the constant current charge size of current can be set by external circuits, and maximum current is 1.5 A.
Above-described embodiment is preferably execution mode of the utility model; but execution mode of the present utility model is not restricted to the described embodiments; other any do not deviate from change, the modification done under Spirit Essence of the present utility model and principle, substitutes, combination, simplify; all should be equivalent substitute mode, within being included in protection range of the present utility model.