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hr(bob) [email protected] hr(bob) hofmann@att.net is offline
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Default Laptop/ drill rechargable batterys.. methods for longer life?

On Jan 5, 6:34*pm, Jim Yanik wrote:
krw wrote . net:





In article ,
says...
krw wrote in
. net:


In article ,
says...
"William Sommerwerck" wrote in
:


I have some from the '60s that still work (I may have finally
thrown them out in the last move). As long as they're stored
flat they should last virtually forever.


What about them drying out?


I don't believe the electrolyte is water-based.
I also don't believe that about "stored flat they should last
virtually forever",as they will still grow crystal spikes that
short out the cell.


It's my understanding that dendrites grow in the presence of an
electric field. *If they're totally flat there should be no growth..


define "totally flat",or just "flat".


Are you saying -zero- volts per cell?


Yes. *That's flat. *They'll self-discharge all the way to zero in a
year or so.


and won't recover,either.



If there's -any- charge on them,they'll grow dendrites.


There won't be charge in them long.


evidently long enough to grow dendrites.



In my experience,NiCds that aren't used regularly go bad quickly.


Either you buy incredibly crappy batteries or you're doing
something bad to them. *


that experience would include my own purchases(like B&D and Makita) and
those of Tektronix for their battery-powered products.

--
Jim Yanik
jyanik
at
kua.net- Hide quoted text -

- Show quoted text -


You can almost always burn the dendrites off with a current thru the
battery of 10 amps or so for a few seconds. The problem is that you
may have to take the battery pack apart to get to each cell to see
which one(s) have developed shorts.