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Ribcracker
11-29-2005, 02:55 AM
I understand that we're supposed to charge our lipos at 1C or less. My charger has fixed rates of 250mah, 500mah, 1 amp, 1.5 amp, and 2 amps. I have some packs that fall between those figures. For instance, I have an 860 mah pack that takes almost 2 hrs to charge at 500mah. I'd be willing to bet that charging at 1 amp would have it done in half the time (about an hour). I have a 480 pack. Would it degrade if I charged at 500? What about a 1320 at 1500? How much can we fudge? Has anyone tried bumping it up a little. I guess I don't want to be the first to try it. That's why I'm asking.
Bud http://www.wattflyer.com/forums/images/icons/icon11.gif

Mattyduk
11-29-2005, 08:47 AM
On my smaller packs I have charged at over 1c. I havent noticed any drop of in performance. I watch them very carfully though.

Just noticed were both from Oxford.

Matt Kirsch
11-29-2005, 01:41 PM
Oxford, on two different continents :)

If you're going to push the envelope, definitely keep an eye on the pack while it's charging. The danger is not in pushing the current too fast when we're talking about such small differences, but in causing the voltage to rise too quickly. This in turn can cause the charger to jump cell count and overcharge the packs, if it's the type that automatically detects cell count.

IMHO, 500 on a 480 is close enough for government work. 1000 on an 860... I dunno if I'd recommend that, but if you do try, keep an eye on the charge and check cell balance more frequently.

Mattyduk
11-29-2005, 03:16 PM
Hmmm yes ;) all we need is Oxford New Zealand.

I hadnt thought of the cell count thing. I have to set mine so no problem there. I would add though I dont do it on my bigger packs though. Not worth the risk:)

Unbalanced prop
11-29-2005, 06:15 PM
What about a 1320 at 1500?

If those 1320s are TP packs, Charlie Wang has stated that they can be safely charged at over 1C with his charger. He is currently doing tests at 2C charge rate to see if it effects cycle life. I don't see why they can't be charged over 1C on another charger, as long as they are well balanced. But as has been mentioned, MONITOR THE CHARGE for safety!!

Doug

Ribcracker
11-29-2005, 09:12 PM
Fellow Oxfordian,
What do you mean by "smaller packs"? Smaller in capacity or smaller in voltage?
Matt,
Thanks for your input. I'd hate to damage my packs so I'm not sure if I want to be the vanguard in such an experiment. Oh, hell...let's try it.
Doug,
My packs ARE TP. But I don't have the balancer for the taps. I'll report back if I have any problems.
Peace, guys,
Bud

Mattyduk
11-29-2005, 09:30 PM
I meant higher value as in money really I wont charge my 5s packs at over 1c. Put it this way if a 25 3s pack doesnt last 200 cycles im not that worried. However a 250 5s pack I take care of.