Lithium battery charging

Lithium-ion battery charging current is required by the most appropriate number?

Rechargeable lithium-ion batteries required (GB/T18287 2000 norms): First of all constant current charging, ie a current will, while the battery voltage is gradually increased as the charging process, when the battery terminal voltage to reach 4.2V (4.1V), constant-current charge change for the constant voltage charging,Dell Latitude C640 Battery, Dell 1691P Battery, Dell 75UYF Battery, that is, a certain voltage, current batteries based on the degree of saturation, with the charging process, continue to gradually reduce, when reduced to 0.01C, that the termination charge. (C is the control current of the battery nominal capacity of a representation, such as the battery is a 1000mAh capacity, 1C charge current is 1000mA, attention mA is not Ah, 0.01C is 10mA.) Why do you think the end of 0.01C to recharge your batteries: This is the national standard GB/T18287-2000 under discussion is arrived at. There used to be common to 20mA to end, the Ministry of Posts and Telecommunications is the industry standard YD/T998-1999 such a requirement, that is, no matter how much battery capacity, and stop current is 20mA. GB 0.01C contribute to charge under the fuller, right through the identification of a party manufacturers benefit. In addition, the national standard provides for charging time is not more than 8 hours, that is, even if not yet reached 0.01C, 8 hours to, and also believe that the end of charge. (No problem, the quality of the battery, should be within 8 hours to reach 0.01C, the poor quality of the battery, wait and meaningless) Lithium-ion or lithium polymer rechargeable battery pack for the best rate of 1C, which means that a 1000 mAh of the battery pack is necessary to 1000mA current fast charge to charge such a rate can achieve the shortest charge time, and will not reduce performance and shorten battery life. For the ever-increasing capacity of the battery group, want to achieve this satisfactory charging rates, increase charge current value is inevitable.

2. Lithium-ion battery charging voltage requirements of the most appropriate number?

Lithium-ion battery nominal voltage 3.7V (3.6V), charging cut-off voltage 4.2V Dell Latitude C640 Battery, Dell 1691P Battery, Dell 75UYF Battery,(4.1V, according to the label batteries have a different design) how the difference between battery is 4.1V or 4.2V: consumers do not distinguish between, and This depends on batteries manufacturers product specifications. Some brands of batteries are 4.1V and 4.2V common, such as A & TB (Toshiba), the domestic manufacturers is basically 4.2V. The 4.1V to 4.2V rechargeable batteries for what will happen: Dell Latitude C640 Battery, will increase battery capacity, feels good to use, standby time increases, but will shorten the battery life. For example the original 500, reduced to 300. Similarly, the 4.2V of the overcharge batteries, it will lower its short-lived. Lithium-ion batteries is very delicate. Since the battery inside a protective plate, we can rest assured it: No, because the shield is the cut-off parameter 4.35V (this is good, the bad to 4.4 to 4.5V), protection board is to meet in case, if the per times are too rechargeable, the battery will soon decay.

Switching Power Supply components:

Q1And switching transformer intermittent oscillator. Chargers Power, the220VElectricity byD1After the half-wave rectifierQ1TheCPole to form a300VAbout DC voltage, after a transformer primary added to theQ1TheCPole, while the voltage is also considered by the starting resistorR2ToQ1TheBPole provides a bias voltage. As the positive feedback effect Q1TheICRapid rise and saturation, in theQ1Into the saturated period, the switch transformer secondary windings of the inductive voltage generated so thatD2Conduction to the load output of about 19VDC voltage of about. Switching transformer feedback winding induction pulses generated by theD3Rectifier,C2Filtered to generate a pulse with the oscillation of DC voltage proportional to the number of submissions. This voltage regulator tube if it is overZ1The regulation value,Z1We turn this negative-rectified voltage is then added to theQ1TheBPole, allows them to quickly cut-off.Q1The cut-off time in inverse proportion to its output voltage.Z1The turn-on / cut-off directly affected by the grid voltage and load effects: the lower the power grid voltage or load current is largerZ1On-the shorter the timeQ1The longer the turn-on the contrary, power grids, the smaller the higher the voltage or load current,D3The higher the voltage of the rectifier,Z1The conduction time longer,Q1The conduction time shorter and shorter.

Charging part:

Mobile phone battery residual voltage (about3V) WasR17,R15After the partial pressure, (1.3V) Increased toIC(AE3102) ③ feet,Dell 1691P Battery, cell phone batteries at the same time by the residual voltageR16LitLED1ByLED1After the voltage regulator(1.8V)Increased toIC② feet, this voltage is lower than theIC③ pin voltage,IC① pin output low. This low level so thatQ2Conduction conduct charge.R8The role is to makeLED1The value of the regulator is more stable,LED1At the same time as power supply instruction.

ICⅡ within the first op amp and ④ footC5Component oscillator circuit. ⑦ foot square wave output from the oscillation, through theR12SoLED2Flashes to indicate charging.

As the battery voltage is increased, as by theR17,R15After partial pressure (③ feet) voltage is higher than theLED1The regulator (② pin) voltage,Dell Latitude C640 Battery, Dell 1691P Battery, Dell 75UYF Battery,IC① pin output high, so thatQ2Cut-off, and litLED3Charge end of the instructions. At this point,LED2Extinguished.

D4Is to prevent reverse damage to the battery circuit;R18Is the over-current insurance resistance;R6Is in the charge after the end of a small current supplement use, the instructions require this time is about0.5Hours.

Multi-function components:

The battery charger using a convenient clip, the two electrodes can be separated from any size, to adapt to a variety of cell phone lithium. Dell 75UYF Battery, PHS was also left in the charger side charging port. A second aspect of the charger, there is a polarity switch, only the battery polarity and charge polarity line, the test lampLED1Only light