Society of Robots - Robot Forum

Electronics => Electronics => Topic started by: Nyuli on January 21, 2008, 11:17:53 PM

Title: Modifying AC Adapter for Charging of 6V Battery
Post by: Nyuli on January 21, 2008, 11:17:53 PM

Alright this is a silly question, but at what current does a battery charger stop being a trickle charger? I have a 6V 300 mA adapter being used to charge my 6V 1500 mA NiMH battery pack. I initially charged the battery about 6 hours because I found a battery amp/volt charging converter and it said to charge that long for those numbers. However, the battery is already putting out under 4.6 V, and the servos will barely turn now on a simple "drive forward loop" program im playing around with. (i only used it for like a minute on the $50 bot) so i think I should have charged it longer. How long can i leave the battery charging without fear of it overheating and failing catastrophically?

Title: Re: Modifying AC Adapter for Charging of 6V Battery
Post by: Trumpkin on January 22, 2008, 12:11:49 PM

When I'm charging my batteries I just check them once in a while with my multimeter

Title: Re: Modifying AC Adapter for Charging of 6V Battery
Post by: Admin on January 25, 2008, 09:27:08 PM

Look up the battery datasheet for charging specs.

If it doesn't have a datasheet, then you can only know by experimentation (eh, it melted, I guess thats too high) or err on the safe side.

Different type batteries have different typical charging rates, in this order from lowest to highest:

lead acid -> NiMH -> NiCAD -> lithium polymer -> lithium ion

finding datasheets of similar batteries should help