How to revive your ni-cd drill batteries with a mig welder
Posted: Wed Aug 01, 2018 1:21 am
I dug out my old battery drill and 3 batteries and found the charger would just start flashing the error led after a couple of minutes so I went digging how to get them charging.turns out they grow dendrites in strands that short the cells and cause them to discharge and make the charger see a dead short .turns out a quick zap with ya mig welder on 30v sorts out 18v nicd batteries like a dream.1st battery 0v and full short circuit on my multimeter gave it a few hits of just the leftover capacitor charge in the welder bought it up to 14v after charging but was dropping volts so gave it 3 proper hits with the mig and it jumped to 16v .drill works a charm can't stop the Chuck on full speed and lasts for ages.2nd battery only jumped to 8v and rapidly discharged it got a bit extra mig treatment and discharged in the drill and recharged its now and 12v works good and I reckon it will get better after a few cycles .3rd one a few quick zaps and a charge after 15 minutes the charger said it was charged tested voltage 20.2v from an 18v battery lol runs the drill fine and so far lasts a long time .will cycle them all again tomorrow .it was all going to go in the bin but now I have a mint drill lol