I've got a Black & Decker Firestorm cordless drill with a A18 slide pack battery. The battery pack has started to fail - is it possible to replace the internals as I resent paying £35 -£45 for new battery pack. I don't want to buy a new drill as there's nothing wrong with it & can't see the point in throwing away a perfectly good drill.

Dave R, August 2009

See my answer to a similar question

Bror, August 2009

I have repaired several NiCd types but not LiOn. They are usually called a Sub-C due to their smaller length than a regular C battery.
They are usually spot welded in a series so you need to 1st find the bad cell w/VOM & then break the weld & solder the new sub-c in its place. Note the polarity! Charge & test.
Hope this helps.

Kevin, August 2009