18 volt ryobi batteries wont hold charge

I want to try this zap thing. I went to do it last weekend and thought it might be a good idea to take the battery case apart and look inside. The battery just needed a couple of connections in the battery soldered. Works great. No zap thing required. I still want to try it, but for know I have to wait.

NiCads stop taking a charge because microscopic crystals build between the individual battery cells (inside the pack) and the leads between them. here is what i have done for my craftsmen NiCad 18 volt batteries to get them to once again hold a charge:

you'll need ~2 to 3 times the voltage that you are using. for instance, if you've got a 14v drill battery that has stopped working, then you'll need 28-42 volts, 18v will need 36-54 volts. i have found 3 car (or motorcycle or lawn tractor) batteries work fine. so i have 2 motorcycle batteries and 1 tractor battery.

i hook these car/motorcycle/tractor batteries up in series. positive from one batt to the negative of the next and so on until i have one positive lead not connected and one negative lead not connected.

something like this: --(batt)+_--(batt)+_--(batt)+

then with safety glasses on i touch the positive lead from the motorcycle battery to the positive tab of the NiCad drill battery with one hand and the negative lead of the tractor battery to the negative tab of the NiCad drill battery (at the same time) and count to 3. i remove and wait a few seconds (5-7) and repeat 2 more times.

once the last ZAP is done, place the NiCad drill battery into the charger and see if the charge light illuminates. if it does, then you have just saved a battery from the land fill and some $$ from your pocket. if it doesn't, then try to repeat it once more, but no more after that.

some word of caution. do not let the the + & - leads of the car/motorcycle/tractor batteries touch each other. that's 36 volts you've got there and will spark/explode.

also, if during the zapping of the dead NiCad battery you hear a "pop", one NiCad cell inside the battery pack has given up the ghost and now the battery is trash for sure. take it to radio shack for recycling. do NOT attempt to zap it again.

use at least 14-16 guage wire (or larger which is a smaller number) to connect the batteries in series and also to zap the NiCad drill batteries.

one final note: do NOT use this method on Lithium Ion batteries. it will not work and may cause injury!!!

good luck.