JT
01-25-2009, 06:59 PM
I originally heard about this a few years ago and have, until today, discounted it as wacky nonsense and potentially very dangerous. Well, it is potentially very dangerous, but it's not nonsense. I got bored and tried this today and instead of needing to buy a new cordless drill, I can now use the same old drill with the same old batteries and so far, it's running like it did brand new. I don't think this shortens the life of the battery, but what do you have to loose when it's already dead anyway?
In a nutshell, what happens to these old NiCad batteries is these things called dendrites (look it up if you need to) grow on the conduction plates inside the battery, shorting it out. Zapping these batteries in this condition literally blows the dendrites off the conduction plates, and the battery is no longer shorting itself out. You will need a high voltage and current DC power supply to do this. In this example, a welder is used. I originally tried this with a car battery recharger, and it did not work. Apparently 12 volts isn't enough to get a good zap going through the battery.
This procedure is primarily for zapping old NiCad battery packs used in drills, old computers, etc. DO NOT ATTEMPT THIS PROCEDURE ON ANY BATTERY OTHER THAN NiCad. I'd hate to see what might happen if this was done on a metal hydride or heaven forbit a lithium battery. You could easily explode a lithium battery this way.
Ok, here is the link to the video. Take proper precautions and wear proper eye and hand protection when doing this just in case. The guy in the video is a little bit cavalier by not wearing a welding glove on his left hand IMO. There is also a potential risk of electrocution if proper safety measures are not followed.
http://www.instructables.com/id/Revive-Nicad-Batteries-by-Zapping-with-a-Welder/
Do this at your own risk, but it did work for me. Now I don't have to buy an entire new cordless drill with batteries or throw down $80-120 for a new battery pack.
I hope this works for someone else out there. It's wacky, but it works. Please let me know if you try this and if it works for you or not.
In a nutshell, what happens to these old NiCad batteries is these things called dendrites (look it up if you need to) grow on the conduction plates inside the battery, shorting it out. Zapping these batteries in this condition literally blows the dendrites off the conduction plates, and the battery is no longer shorting itself out. You will need a high voltage and current DC power supply to do this. In this example, a welder is used. I originally tried this with a car battery recharger, and it did not work. Apparently 12 volts isn't enough to get a good zap going through the battery.
This procedure is primarily for zapping old NiCad battery packs used in drills, old computers, etc. DO NOT ATTEMPT THIS PROCEDURE ON ANY BATTERY OTHER THAN NiCad. I'd hate to see what might happen if this was done on a metal hydride or heaven forbit a lithium battery. You could easily explode a lithium battery this way.
Ok, here is the link to the video. Take proper precautions and wear proper eye and hand protection when doing this just in case. The guy in the video is a little bit cavalier by not wearing a welding glove on his left hand IMO. There is also a potential risk of electrocution if proper safety measures are not followed.
http://www.instructables.com/id/Revive-Nicad-Batteries-by-Zapping-with-a-Welder/
Do this at your own risk, but it did work for me. Now I don't have to buy an entire new cordless drill with batteries or throw down $80-120 for a new battery pack.
I hope this works for someone else out there. It's wacky, but it works. Please let me know if you try this and if it works for you or not.