Batteries are FUBAR, reconditionable? YES!

[Tankdude]

It is like flogging a dead horse. I had the problem solved last night. Called on one of the EE and he said he has a cycler which we can use to correct the battery problems.

The only guys that gave me any info was Drake and Mysteryfish.

"I also have done so. Taken a 1700mAh battery that was holding 120mAh back up to full capacity..."

That tells me the batteries are not to far gone. Which is what I asked in the first place.

I don't need any help from grey on amperage and voltage lessons. Gas tanks or what ever he implies, according to him the SAS G3 is a real gun and is "insane" as he calls it. I take what he says with a pinch of salt so small it can be taken with another pinch of salt.

[Tankdude]

update: Got a supernova 250s from a friend.

First Discharge was 53mah
then charged to 147 then D of 136
then charge to 73 and then D of 74 and
finally it took a charge up to 23% and is discharging right now.

Just had to break the shell. One down and two to go.

Good little charger, unfortunely it is not automatic and I have to press charge and then discharge myself.

[Scarecrow]

Originally Posted by Greylocks

If the equipment you have cannot measure amperage, or you dont even know what that is, open your wallet and get yourself a really good computerized charger.
That's cheaper than tossing batteries away.

You don't know what the hell you're talking about Greylocks. The NPT charger is a perfectly good charger, particularly for dealing with batteries that have been fully discharged and stored over time. Stop recommending he spend $200 on a charger that is nothing more than a peak charger with a digital readout that does nothing more than tell him the power that the charger is injecting INTO the battery. It doesn't address the battery behaviour itself and the information is therefore useless in these circumstances.

What he needs is a device that reads the battery state under load to determine if the battery is still good or not. If the battery cannot push the amps, it does not matter what the voltage is. If the chemistry of the batteries are compromised, I don't care what kind of charger you have, it won't bring them back to life. If the battery cannot HOLD a charge from a discharged state, the battery is in all likelihood toast. I would recommend trying it on a peak charger using brute force and see if it behaves differently, but I suspect those batteries are toast.

There is the possibility that the prior owner of the battery used a peak charger, charged them way too fast, generated a ton of gas inside the battery and separated the internal battery chemical materials. Check the cells for pressure signs such as expansion of the metal ends or if its a full metal housing, the housing itself. Also look for cracks. While not diagnostically conclusive, it may help you determine the problem if there is expansion fast enough to deform the housing.

NiCd and NiMH batteries are constructed from materials that have different coefficients of thermal expansion and different coefficients of compression. The positive and negative plates are composed of dissimilar metal compounds. The separator is a polymer (plastic) material. The electrolyte is a viscous liquid and the battery case is usually made of a plated steel alloy. Heat and pressure associated with the charging process cause mechanical stresses that cause batteries to wear out if heated plastic separators in the batteries expand more than the surrounding plate materials and the case. The soft, plastic separator is most vulnerable to the pressure that results from gas generation associated with overcharge.

http://www.bbbastard.com/nptdetails.htm

Originally Posted by Tankdude

I don't need any help from grey on amperage and voltage lessons. Gas tanks or what ever he implies, according to him the SAS G3 is a real gun and is "insane" as he calls it. I take what he says with a pinch of salt so small it can be taken with another pinch of salt.

Yeah, a 20lb bag of salt. The motor draw (amp rating) and the tightness of the mechbox (friction) dictate power consumption. While AEGs vary, they don't vary that much from model to model - only from upgraded box to upgraded box and how hard to motor has to push to move the gears and thus the spring.

But all that is putting the cart before the horse. You're on the right track, keep playing with the cycler. The ultimate question though is what amps can the battery pack supply when under load. If you can answer that, you can generally tell if the batteries are damaged or not. The only reason I am skeptical is that I've not seen an NPT charger NOT solve a battery memory problem. In fact the principle and design are not unsimilar to the cycler you are using.

[Greylocks]

Psst, I meant the real gun. It was built just to see if they could make a .308 full auto gun that small. Look it up before dismissing the information.
The insanity part was the extreme amount of muzzle blast.

But hey, that requires research instead of flaming the old guy.

[Tankdude]

Final results.
Battery 1 is at 3100 mah from 170mah
Battery 2 is at 3600 mah from 200 mah
Battery 3 is at 3600 mah from unknown, but most likely the same.

Mind you these are 3300 mah pack, but I am not going to argue with the machine. If it can pack 300 extra mah in there then so be it.

[Skippy]

Originally Posted by Tankdude

The word you guys are look for is capacitance.
Check the capacitance of the cells.

Cells do NOT have capacitance. Capacitance is the measurement of stored charge in a CAPACITOR.

You need to find out how long they sustain their peak current, which means using the ampere setting on your multimeter. I -think- what you have to do to check that is plug the battery into the load (either your car or a resistor bank of the same ohms) and check it's maximum current, and how long it sustains it.

(NOTE: This is based on my limited experiance in electronics. I'm studying residential electrical installations, not electronics, so I'm probably wrong in the methods I gave, but all the other posters are correct in saying that you need to check amperage.)

EDIT: Dammit, I got beat to it, and better.

[Mysteryfish]

Werd!

[Scarecrow]

Originally Posted by Tankdude

Mind you these are 3300 mah pack, but I am not going to argue with the machine. If it can pack 300 extra mah in there then so be it.

Let me know the results of fielding it with a gun, I am really interested to know how it goes - what brand and model of cycler are you using? Thats the first time I've seen an NPT charger not fix what appears to be a memory problem, if your readings are correct.