Anyone give me any advice on how too revive some 3am 24v nicad packs? Their fairly old but are still holding some volts, yet I don't know how to treat them, good hard cycle or a low amp slow one?
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Anyone give me any advice on how too revive some 3am 24v nicad packs? Their fairly old but are still holding some volts, yet I don't know how to treat them, good hard cycle or a low amp slow one?
You need to cycle them at around 4amp charge ish it don't matter too much, you propably have a few cells gone so you will have to test to find them 1st and replace them as cycling won't work with damaged cells in the pack.
I got so pissed off doing this so I changed to a123s as the charger automaticly balances.
So take off all the heat shrink and test all the cells, if they read 1.2v then their fine, or could I get away with testing the whole pack and buying enough cells to replace them all, then find the old cells?
I've got all the chargers for Nicads so would like to try and use them, won't be cheap but probably still cheaper then buying A123 chargers and batteries
no dont take heat sink off just yet
measure voltage ie 24v
if 24v then charge fully then discharge 3 times or run the bot down street till dead then charge
normally a good charger can cycle theses
if u dont have say 24v then yes have to strip
I've checked my packs and one is 21.6v, the other two are about 16v, so go and take heat sink off and try and find some replacement cells?
They hold 24v after being charged but soon drop back off
16volts is very low, if you have that many cells gone, the rest won't be far behind. You will struggle to get hold of the cells nowadays as well.
Found a source of cells, around £5 a cell, don't know if it's worth a shot and try too get the Nicads back in working order or stick with SLA's till I can afford A123 packs and chargers, though I'm bot sure how much it would be for 3 12v packs
http://www.ebay.co.uk/itm/10pcs-New-Ori ... 211wt_1114
you'll want atleast 3 packs of 8 cells so you're looking around £130 for batteries plus another £100 for a cellpro 10s charger.
Not as bad as I though it would be but would 2300mah be enough?
3x 2.3ah = 6.9ah. That should be enough for bulldog as you're only running Bosch 750s on 24 ish volts.
I run 4 packs of 2.3ah, normally use around 5amp at the most in fights so 3 packs would be enough.
So 24 cells would make me up 6 12v packs as each cell is 3.3v? The old set up was 3 12v nicad packs all into 3 different plugs, so I could make up enough to have a full set of spares put of 24 cells?
Or better to make a 2 24v packs? Can run 24v worth of hawkers on a single lead out of the 3 but still trying to get my head around the wiring and how many packs I could/would have too use and at what voltages
3 packs of 8 cells!! The three packs Wired in parallel to give 26.4v 6.9ah
May have to re-do the wiring slightly then to adapt for the new packs
anyone know of any good chargers that are not £100 each, bit steep for £420 in total for a conversion so want too bring that cost down a bit really
How viable would it be to use 8.4v nimh packs of the same 3000mah? would need 3 packs of 3 so 9 packs in total, but comes out at under £200?
http://www.wheelspinmodels.co.uk/i/70479/
Just exploring different ideas here, dont want to run SLA's forever :lol:
How Is £120 + £100 £420?
You could probably use turning accucel 8s as you're only running 8s packs.
Though I would need a charger per pack, 3 packs so 3 chargers?
Most people just use 1 charger for there a123s i beleive.
Split it off too allow for 3 feeds of a single charger?
Dont charge your batteries in parallel. Everyone i know whos running A123s is running seperate chargers, dont see any other way to balance them.
Those NiMh wont deliver anywhere near enough current, probably only 40amps, so you would be looking something like 6 packs of 24v (so 18 packs altogether) to get any usable current out of them.
If weight isn't an issue i would stick to SLAs, much easier.
Have to find some good scales and see if weights an issue then
the behemoth guys charge their a123's while they are in paralell, dont see how it can balance properelly.
lol balancing A123s. I never bothered when I ran them in hornet. Rewired that battery pack up in parallel since and charge it like that with no issues at all. Just gotta make sure they're balanced when you make up the pack.
Because your a123's were really reliable Gary? lol
A123's suck, go lipo or go home :proud:
I would go lipo but currently banned in HW's :angry:
Hannibalito 3 has been running A123 since 2007 and not a single problem with them.Quote:
Originally Posted by mr_turbulence
So I could charge 3 packs off one charger? Trying to figure out what can be done here so I can decide what too sell
just trying to clarify if it can be done, if so may put some stuff up for sale tonight
Send a message to kane, I'm sure behemoth charge 4 packs in paralell, at about 30 amps !
the A123s were fine dave. It was stalling a mag on them that caused that pack to blow.