On Fri, 17 Jun 2011 17:09:12 -0700, "Bob F"
wrote:

wrote:
On Jun 17, 11:35 am, "hr(bob) "
wrote:
On Jun 17, 9:58 am, "
wrote:

On Jun 17, 10:04 am, RicodJour wrote:

I'm interested in experimenting with trying to revive some old NiCd
batteries by zapping them and I ran across this on YouTube. Good,
clear video about using two other good NiCd batteries to revive the
dead one.

http://www.youtube.com/watch?v=1e8hHLyXAyQ

R

I wonder if it works how much more life you get out of them.
I saw this a while back when I had a driver/drill pack that went
bad. Finally decided that for $20 I could get new batteries on
Ebay and just rebuild it.

What the OP is talking about is using a low-impedance power source to
burn open the whiskers that sometimes form on older NICAD batteries,
especially when they are left unused and uncharged for long periods
of time. Once the cells start whiskering, they almost always are
prone for it to happen again, the best thing to prevent/stop this is
to keep them permanently on a trickle charger. I have some very old
nicads, perhaps 30+ years old, that I still use in some tools that I
keep on trickle chargers. I know I am using power to keep them
charged, but the convenience of always having the tools ready when I
need them outweighs the small cost. When they were new, they were
very expensive so that is another reason I hate to discard them.

Actually I've read just the opposite. That leaving them completely
discharged is the best way to store them.

I wouldn't believe that for a moment.

According to Panasonic, storing NiCads should be between 10 and 30
degrees F, and charged at least once a year. Never store the battery
dead.
NiMh batteries are a different story and can be stored long-term
either dead or fully charged, According to both Sony and Duracell you
may need to "reactivate" them by charge cycling - long term storage
between -20 and +35 F, 50% RH.

DO NOT store dead with a load connected.