Bringing back old batteries

[l_bilyk]

I got a pair of NiCd batteries for my drill and it seems like they are just about done. They don't hold much charge any more. I don't think there are any dead cells though. Will consectuive cycling break up the crystals that form? What if i give them a good whack? :)

Damn things cost like 80 dollars... at that rate i may as well buy a new drill

[Bradley Miller]

We used to "zap" the RC batteries with 12 volts at high amperage (30+ amps) to knock the crystals off. There was also a zapper function on the old Victor HIQSr computerized charger that with the right parts would put a high voltage zap into the battery (90 volts???). This all of course was on a single cell, not a battery pack . . . if you've got the thing torn down to get at a single cell, you might as well replace all of them. :-) I don't know how exactly the reman batteries work, whether they reuse the stock case or what, but that might be worth looking into.

[Luckydevil]

BoostAddiction had posted this link in another thread...

http://www.voltmanbatteries.com/batteryrebuilds.htm

Only $35 per battery for 12v-18v. That is who I'll be using when I need some tool batteries rebuilt.

[l_bilyk]

We used to "zap" the RC batteries with 12 volts at high amperage (30+ amps) to knock the crystals off. There was also a zapper function on the old Victor HIQSr computerized charger that with the right parts would put a high voltage zap into the battery (90 volts???). This all of course was on a single cell, not a battery pack . . . if you've got the thing torn down to get at a single cell, you might as well replace all of them. :-) I don't know how exactly the reman batteries work, whether they reuse the stock case or what, but that might be worth looking into.

Hmmmm so you're telling me to connect it to a car battery charger and set it on boost?

[l_bilyk]

BoostAddiction had posted this link in another thread...

http://www.voltmanbatteries.com/batteryrebuilds.htm

Only $35 per battery for 12v-18v. That is who I'll be using when I need some tool batteries rebuilt.

$35!! thats not bad.. i may just have to keep this drill

[Bradley Miller]

Hmmmm so you're telling me to connect it to a car battery charger and set it on boost?

Not the whole pack -- just individual CELL. (Cell + cell = battery pack)

[l_bilyk]

Would it make a difference if you zap the entire pack?

[Bradley Miller]

Would it make a difference if you zap the entire pack?

When we "zapped" a cell, we were bringing high voltage or high current to it. A 1.2 volt cell with 12 volts on it is "zapped". A battery pack that is 14.4 volts, or so, on a 12 volt battery isn't going to really be affected. Even if its only a 9.6 volt one, putting it on the 12 volts is going to be like a minor charge to it . . . not a zap. Like I said, to do it, you'd have to tear the pack down and zap each cell, or just find the bad one and replace it.

[jfelbab]

When we "zapped" a cell, we were bringing high voltage or high current to it. A 1.2 volt cell with 12 volts on it is "zapped". A battery pack that is 14.4 volts, or so, on a 12 volt battery isn't going to really be affected. Even if its only a 9.6 volt one, putting it on the 12 volts is going to be like a minor charge to it . . . not a zap. Like I said, to do it, you'd have to tear the pack down and zap each cell, or just find the bad one and replace it.

Isn't there a risk that the cell could explode?

[Bradley Miller]

Well, it's not going to be a "take your head off" kind of thing . . . we'd also hit packs with 10 amps (SCR 1200 and 1400's) and Sanyo didn't recommend that either. GRIN