Can I actually "ZAP" my Nicads back to life?

Tom Baugues

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Lafayette, Indiana
Ok, many of you here are going to think I have lost my mind and maybe I have but I have been reading several articles tonight about how to bring my old dead rechargeable Ni cad (cordless drill) battery packs back to life. I have read everything from smacking them hard with a block of wood to "zapping" them with higher voltages to placing them in the freezer. The theory is that the cells have produced "crystals" within themselves and therefore short themselves out. By zapping them you break down these crystals and the cells will then again take a charge and continue to work again. The idea is to apply twice the voltage for just a few seconds then check the voltage with a meter until it responds with about 2 volts over the rating of the pack. Has anyone ever tried this?
I read all this here on the INTERNET so it MUST be true. Right?
Yes I know the battery will not be covered under warranty anymore and yes I understand that they can overheat and explode. So I am not suggesting to anyone to try it. I'm simply thinking of trying this for myself.

Here is a link to one of the places I was reading. http://ysuusy.com/easybatteryfix.html
 
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I've done it to my 2 ridgid 18 volt nicad batteries. I used my mig welder to do it. I used a setting that had about 24 volts on it and then tapped it across the terminals. Before I did it the batteries would not take a charge. Now they will take a charge and would only charge to about 13 volts. After they sat for a few more months I did it again with another 18 volt battery and now they charge to their full 18 volts. Why that is I don't know but All I know is that I have 2 more batteries to use again.:thumb:
 
I've not tried it, but if the packs are dead already, it doesn't seem like you have anything to lose by trying it. (Taking appropriate safety precautions, of course.)
 
I used to race RC cars back in the day with nicad batteries, adn there were a ton of tricks to charging and conditioning, because even .1v difference in a battery pack or 5-6 seconds life made a difference in winning/losing.

We did dead shorting on packs, but you had to link each cell individually or there are side effects. Also there were battery "zapper" devices to get a little extra charge out of a battery pack. The results didn't last very long, only a few charges. A lot of people thought it shortened the overall lifespan of the batteries also.

Usually when a battery pack dies, really you're only losing one cell out of it. It would be nice if it were easier to open/access the nicad packs and replace the bad battery.
 
I recently tried it on 4 18 volt battery packs. Tried it with 36 volt strung together battery packs, auto battery charger, MIG welder. A little better for a couple of charges, then back to useless.

Cheers,
 
I'd save the time and upgrade to the Lithium, if its available for your tools. I did, and I'm not going back. I still have my original two Ni-Cds that I keep around, but I haven't bothered to charge them in months. They'll be relegated to the fan and radio once spring rolls around. The actual tools get the Lithiums.
 
i tried it on some milwaukee nicads and it didnt make no difference at all. packs were still weak and charge didnt last no longer. personly i think its a waste of time and the dangers involved arent worth it and my spelling sucks right now.
 
It's intresting that you replied to my post today.
I just told my father about this a few days ago so he gave me a battery that he had that would not charge and I have gotten it to now take a good full charge.
I will say that I have also gotten one of my two batteries to also come back to life. The other pack has not responded at all.
So, I have tried this on three packs in the past couple weeks and two of the three are now back in service.
My experience with this is that it takes several tries for the pack to respond. I keep a close eye on the pack to ensure that it does not get hot. Then the more you charge then drain the pack and repeat...the better it gets.

All I can say is that I was going to have to go buy a new battery pack and now.....I don't.
 
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