Charging a Battery

[technorama]

HI
I would like to know when a rechargeable battery is charged whether the voltage or the current should be maintained constant?

Please help.

 

[itsmoked]

Your question has so many holes in it I could drive a truck thru it!!

You need to be MUCH more specific. Otherwise the answer is yes or yes, or yes and no, or no and yes, or no and no.

Keith Cress
Flamin Systems, Inc.-

http://www.flaminsystems.com

 

[ssn596]

Generically
IF as you stated "once charged"
then you will maintain constant voltage.
Of course since it is charged you would also maintain constant current at or near zero since it is charged but we wont get in to trivial details

Dan Bentler

 

[TurbineGen]

It depends on the battery type mainly. Most charge at a constant current until the battery is near it's peak voltage and then the current tapers off.

Lithium batteries should not be charged over 4.2 volts per cell. Lead acid batteries are usually around 2.2 volts per cell at peak voltage (at least the ones I've worked with). You can "trickle charge" the lead acid batteries at a reduced rate once they are near peak. Do NOT over charge lithiums though.

NiCd and NiMH batterys can utilize peak drop charging. That is the voltage peaks (around 1.6 volts per cell) and then falls slightly (maybe .05 volts per cell) at full charge.



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If it is broken, fix it. If it isn't broken, I'll soon fix that.

 

[advidana]

Buy a battery charger that is rated for your battery that you are using. Make sure the charger you buy has sonme type of indication on it if it is fully charged. Don't charge it with a power supply. Use a battery charger, it has special features designed to charge you battery properly.