glad to see two of you want to save money.
this is not a new process, it was produced for NASA many years ago because thier batteries would not last in space on long missions, the batteries would go dead just like your power drills.
So they came up with a method to revitalize them in space.So having said that lets get started.
First a ni-cd battery cell is a 1.2volt joined together to make the size required. For our purpose we are using a 12 volt dewalt say 1500mah
but the mah is not important. A battery when it gets tired crystals form inside causing shorts reducing power to the point it goes dead,you have to get rid of the short, there is several ways but we will use only one here.
Our 12 volt battery has 10 cells each 1.2volt connected in series ,10 times 1.2=12volt.
unscrew the screws from the case and remove half that fits your charger being careful not to damage cells or connections inside , take note of which is positive and negative terminals.
Now for the list of items you will require for the job.
a digital voltmeter
two 12 volt car batteries
one car booster cable with good clips (only one cable required not the set)
two number 12 gauge wires with clips on one end only, make them one positive one negative or at least mark them so you now which is which,
strip the other ends so you have about 1/2 inch bare
charge you battery in your charger to the best it will charge and take a reading with your voltmeter,we asume this was a dead battery so lets say your voltmeter has a reading of 3.84 volts after charging ,its dead right! WRONG it has those crystals in the way of taking a charge so follow these steps and be amased.
one- with your car single cable booster and the two 12 volt car batteries
connect one end to th positive post on the first battery and the other end to the negative of the second battery.
Two- take the two 12 gauge jumpers and connect them to the batteries,the positive to the positive and the negative to the negative, you should only have two striped ends left don't let them touch anything please
NOW take your power drill reading 3.84 volts and put it close to the jumper leads ,take the positive jumper and hold it to the positive terminal of your 12 volt battery relax nothing will happen until the negative is brought into play .
now take the negative jumper and brush the negative terminal two or three times you will get a small spark at the negative side,
now check yor voltmeter reading you probabaly have6 or 8 volts repeat process until you read 13 or 14 volts you are allowed 10 percent over
put your battery back together and try it in your drill
HAVE FUN post your thouhts when you done
CRAZYCANUCK