Draining batteries

AcidRainLiTE · Post by **AcidRainLiTE** » Sat Jan 14, 2006 6:02 pm

I want to drain some NI-MH batteries to run them thought a few cycles so they will accept full charge. Can I just stick them in a battery holder and connect the + and - with a resistor in between? If so, what ohm resistor should I use to drain it? (7.2V total: 6 AA 1.2v 2500mAh in series). Thanks.

Post by **gannon** » Sat Jan 14, 2006 6:06 pm

I'd say you should use a 10 ohm heatsinked 6W resistor

daguuy · Post by **daguuy** » Sat Jan 14, 2006 6:07 pm

don't you only have to do that to nicad?

Post by **Sparkfist** » Sat Jan 14, 2006 7:02 pm

daguuy wrote:don't you only have to do that to nicad?

Yeah... Unless your parinoid about battery memory exsisting in Li-Ion. Yeah I know it sounds stupid, but that's what my brother does with his phone.

AcidRainLiTE · Post by **AcidRainLiTE** » Sat Jan 14, 2006 7:23 pm

I am draining them because they are brand new and NI-MH batteries that have not been used in a while or are brand new don't fully charge until they have gone through a few cycles.

xxxeagle · Post by **xxxeagle** » Sat Jan 14, 2006 8:30 pm

Just hook them up to something and use them up that way you get some use out of them.

timmeh87 · Post by **timmeh87** » Sat Jan 14, 2006 10:54 pm

i personally dont believe in all this crap about memory and accepting full charges andd such things. ive read several well written articles debunking such things.

http://www.dansdata.com/gz011.htm

anyhow, if you read and fully underswtand the part about voltage depression, and you still want to do that, gannon has the right idea. he says heatsinked for a reason; that mofo will get HOT.

V = I R

V is 7.2, and you want your I to not be more than about 2. so figure out your R