On 6/17/2015 2:39 PM, sms wrote:
On 6/17/2015 2:39 AM, mike wrote:

FWIW, I have never purchased a used working drill with a usable
battery...that's
why they're for sale, it costs more for a battery than a new drill.
If they broke the drill, sometimes the battery is ok.
So I have a box full of mismatched drills and batteries.

A lot of the power tools still use NiCad batteries which can be fixed
when they develop a short. You need to zap the individual cell with a
high current from a large capacitor, or a high current DC power supply.
Doesn't work for NiMH or Li-Ion.

From the tone of a posting, you can often infer the level of experience
and equipment available to the poster.
I try to present input in a language and level of detail appropriate
for the situation. Based on the question, I'd bet that the OP doesn't
have the stuff required for safe dendrite blasting.

FWIW, I've never had much luck blasting a battery.
I have had some limited success blasting individual cells.
A dendrite is a short. When you blast it out, you make
the hole in the separator even bigger. Self discharge makes the
pack useless unless you charge it and use it immediately.
And the short returns eventually. If you're not paying close attention,
you can ruin the new wall wart too.

I've tried replacing individual cells from another bad pack.
Never had much luck with that either. If the packs are abused and
shorting, it's just a matter of when the next domino will fall.