I’ve got a 12v nicad dewalt drill driver that is still ok but batteries are kaput - after reading this I think I might try and source a couple of batteries to revive it as it was actually a pretty decent little drill.I’ve ordered 3 different sets of batteries
18v for my new (ish) dewalt
9.6 for an old but unused makita, and
14.4 v for an old dewalt
well the 14.4 has arrived, fully charged now and the drill lives
I’ve got a 12v nicad dewalt drill driver that is still ok but batteries are kaput - after reading this I think I might try and source a couple of batteries to revive it as it was actually a pretty decent little drill.
If a manufacturer uses 6 cells (each 1500 mah@ 3.4 volt ish) with a 10 amp maximum current draw per cell on a 1.5 ah pack he places them in series, so the pack will deliver 1.5 ah @ 18volts and 10 amps
However, chances are the higher capacity batteries (lets say 3ah) use the same cells, but double the amount. This would give 12 x 3.4 volts, so roughly 40 volts @ 10 amps But as he only needs 18v he does not put all 12 in series.
He will probably make 2 sets of 6 cells, with each set of 6 connected in parallel.
This system will give double the amp hours, but also double the maximum current draw as well.
That's my fear of cheap copies. I've heard of 18650s going on fire when charging.To this day though I'm wary of leaving them charging unattended