Battery and LED connections

[kobre98]

Hi,
I have 11.3 volt 7AH laptop battery, I was able to connect 12v leds to it, and they work just fine
but I have some questions,
First regarding charging the battery, what is the charger characteristic that I need to charge this battery correctly, I know that 12v battery can work, but what about the ampere, and what is the acceptable range for charging it, regarding voltage, meaning can a 20 volt charger affect that battery badly or it has no affect at all ?!?!
i.e I need a small lesson on how to charge a battery, and what is the best charger characteristic and limitation ?!?!

Second how can I make automatic cut off circuit that allows that battery to be charged and then the charger is automatically disconnected using a relay or so.

thanks in advance

 

[Ogu Reginald]

Re: need help with battery and led connections

Welcome, for you to charge any battery and get a good result and make the battery last long as well, the voltage output of the charger should not be higher than 1.19xvoltage of the battery to be charged (1.19x11.3V) which is about 13.45V.
Using 20volts will destroy the battery.
Don't worry if I settle down today, by tomorrow morning I will upload the circuit you requested for the cut off.

 

[Ogu Reginald]

Re: need help with battery and led connections

See the circuit
http://
obrazki.elektroda.pl/2398256300_1388304877.jpg

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http://www. obrazki.elektroda.pl/4178781900_1388305077.jpg

 

[Ogu Reginald]

Re: need help with battery and led connections

https://obrazki.elektroda.pl/4178781900_1388305077.jpg

 

[DeepOne]

Re: need help with battery and led connections

Usually use constant current/constant voltage method.
Raising voltage above 13V6 for long time is not advisable for such batteries since this causes decomposition of water and shortens cells lifetime.

 

[kobre98]

Re: need help with battery and led connections

thanks for the help guys
but I couldn't find the IC in the drawing could you please provide me with a circuit diagram that contains amplifier and can do the job ?!
or any other circuit with a more common and easy to find components

 

[Ogu Reginald]

Re: need help with battery and led connections

thanks for the help guys
but I couldn't find the IC in the drawing could you please provide me with a circuit diagram that contains amplifier and can do the job ?!
or any other circuit with a more common and easy to find components

Check my own circuit, the values of the components are there and they are easy to find. The op amp is Lm324 or any other op amp.

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https://obrazki.elektroda.pl/4178781900_1388305077.jpg

The above is link to my own battery monitor/ cutoff.

 

[kobre98]

Re: need help with battery and led connections

thanks but can you explain to me how to use it if I want to charge 6v and 12v battery, meaning how can I change the value of the cut off ?!

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in addition to the fact that I really need the transistor and diode values, some Items values are not included ?!!

 

[Ogu Reginald]

Re: need help with battery and led connections

thanks but can you explain to me how to use it if I want to charge 6v and 12v battery, meaning how can I change the value of the cut off ?!

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in addition to the fact that I really need the transistor and diode values, some Items values are not included ?!!

Hope it is my circuit you are talking about?
The only component on my circuit without a value is transistor, you can use 2N2222 or BC108. The LED is just an indicator, you can use any colour.

For using the circuit for the battery voltages you mentioned, just adjust the variable resistor and use voltage divider rule for calculation.

 

[kobre98]

Re: need help with battery and led connections

I'll try it and report back to you.