battery charger with mobile phone charger

[microlab]

Hi all

can we use the mobile phone charger as the battery charger?
i'd a mobile phone charger with output 5.4V,1000mAh
and a battery of 3.6V,800mAh. the battery is of 3x1.2V AAA battery.
can we make a charger adding a few components to the charger?
what could be the possible way?


thanks and regards

ml

 

[shuzonudas]

if you directly connect like this :
mobile phone charger(+)------battery(+)
mobile phone charger(-)-------battery(-)
it'll start charging.
for safety reason you can add a 10ohm,22ohm or 47ohm registor.
if it is a lion battery, there is a chip in the battery "do not remove the chip".
use a multimeter to monitor the battery if it exceds 4.2v(lion),4.5v(1.5*3-nicd) then stop charging.

happy charging.

 

[microlab]

hi

it's a NIMh battery
which is 0f 3.6V 800mAh AA type(1.2x3).
there are 3 pins from the battery. i think the extra one is for battery charge monitor.
how can we predict the resistance to be used?
can we make a circuit which automatically stop charging when the battery is fully charged instead of using the multimeter?

regards


ml

 

[shuzonudas]

yes you can if you know microcontroller programming well.
use low cost "PIC 16F628A"
it is not so easy task.

the equation for your problem
volt =res X amp
>res=(volt/amp)
>volt=(5-4.5)=.5 ;charger volt=5 volt ,4.5 volt=full charging volt
>amp=.05A (assuming)=50mA
>res=(.5/.05)=10ohm

if you use this circuit it'll take about 20 hours to fully charge.
if you increase amp the battery life will reduce.
if you want quick charge use expensive batteries like "GP power bank"
4 battries(1.5v) + 1 charger =3500 taka; 70 taka = 1 doller
it takes around 40 minutes to fully charge those batteries. i was satisfied with those products ,now there are rechargeable battries with every products.

and what you want to do with those battries ??

 

[microlab]

hi
the battery is powering some remote control system. actually they are used with the normal normal batteries. what i thought is to replace the same with the rechargeable batteries.can you provide some more details? like the schematics with the PIC? i think i can do the coding.

thanking you

ml

 

[roltex_rohit123]

if the battery is of the Li-ion type dont charge it above 4.2 volts or it will go bad or even explode!! if it is of the Ni ion then it could bear the voltage, but you need to reduce the current from the charger. maximum current reduces battery life.