Bringing back life into nimh???

jdmsiref9 · 10-12-2009, 08:59 PM

Hey guys... i was wondering if its possible to bring back life into some old packs i have had in storage for about 8 months. they are integy 3000nimh battery packs. Any tips???

Razathorn · 10-12-2009, 09:04 PM

Quote:

Originally Posted by jdmsiref9

Hey guys... i was wondering if its possible to bring back life into some old packs i have had in storage for about 8 months. they are integy 3000nimh battery packs. Any tips???

They've probably sat long enough that their separator is damaged and they will self discharge very quickly and at odd rates. All that means is you must run them reasonably soon after charging (like within a day with a re-peak before the run) and you must per-cell discharge them (probably to zero volts) before charging each time. Other than that, they probably just need a good zap with the charger to wake them up (charge for like a second or two at 5 amps), then equalization all the way to zeros on a discharge board, then fast charge (5 amps or so) while monitoring temps. They're probably going to run nutty well but just require some attention. I have packs like this and they are great but you just have to equalize discharge them the night before and then charge them day of, then re-peak before run, and re-use after a good 30min to hour cool down. They absolutely rock still.

RC Dad · 10-13-2009, 09:59 AM

I've found that a good way to bring them back is to charge very slowly, like 2 amps, the first time you charge them fully.

Dave Barber · 10-13-2009, 12:28 PM

It would help to cycle them a couple of times.

The Captain · 10-13-2009, 08:01 PM

Quote:

Originally Posted by RC Dad

I've found that a good way to bring them back is to charge very slowly, like 2 amps, the first time you charge them fully.

This is true, but more like at .5 amps. Check www.batteryuniversity.com lots of good info there.

JeromeK99 · 10-13-2009, 08:08 PM

If all the cells are still good... no real reason they shouldn't be. A few cycles (charge and discharing) should bring them back. If after about 3 or 4 cycles they are not able to take a 4-5amp charge without false peaking, you might have some bad cells... Equalizing cells before charging will get you more life out of old cells as well. If they aren't any good.. now is a good time to move to LiPo.. Prices are getting better. Orion just release a new 25C sport line that looks pretty good.

Jerome

jdmsiref9 · 10-13-2009, 08:46 PM

Quote:

Originally Posted by JeromeK99

If they aren't any good.. now is a good time to move to LiPo.. Prices are getting better. Orion just release a new 25C sport line that looks pretty good.

Jerome

I have 6 Orion Lipo packs already. i just found my case of 6 3000nimh sidexside pack. i figure i can use them for bashing. but last time i tried to run them they false peaked a couple of times.

I did on the other hand zap them... and it brought some power back. so... i think im gonna cycle them a couple more times to see if i can get that punch back. Thanks guys for your replies. Your tips have helped me get these stubborn packs alive again!!!

The Fox · 10-15-2009, 07:47 PM

I just brought back to life some 3300mAh packs that have been sitting over 2 years. I just set up me checkpoint and Ice charger to a cycle discharge/charger. I set the charger at 1amp charger and 5 amp discharge. Next after it only took 200mAh, I started to go up to 3.3 amps followed by a 5 amp discharge. After it took a few more mAh I upped the charge rate to 5 amps and upped the discharge to 10amps. After about 6 cycles the packs would hold 3316 mAh, the same as the labels says.

Nick