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werty werty is offline
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Default Battery memory( NiCad) Pulse charge it !!

1) Pulse charge and it will return to full energy if it is
still in infancy .

Never deep cycle any battery . Batterys die for being NOT fully
charged . Leave them discharged is to shorten life .
----------------
2) NimH and Nicad lose 10% in 1 day , Li-Ion lose 1% .
I gambled on 100 NimH "LenMars" 2.5 aH AA's
from Buy.com .. 25% loss in 1 day , load tested OK ,
i tossed them , not worth my time .

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more ........................
Pulse charge a nicad and it "loses" its memory , return full energy
..
......... a 4 amp pow supply with a simple Resistor works great .
C cell ( NiCad ,NimH) , as in drills , can take 2-3 amps til
about 1pt36 vdc
(((Linux crap apps ! Konquerer ..Cant see the text , too small , no way
to
change it so i use pt for decimal point ))))))))

1 ) so pulse with a very low Z pow supply at 1pt48
to 1pt5 vdc
per cell and a Resistor of 0pt25 ohms . Theorectically ,
you must select R ( 0pt25) carefully , use scope to see the
lighter
amps , for it will heat up if too much amps above 1pt38 vdc .
2) but since current is so hi and pow supply is
likely to
help the current limit anyway , just measure the current above
1pt36 to 1pt37 vdc and adj the supply
Voltage instead of doin the Resistor .
Now the resistor limiter is inside your pow supply and you can
simply
vary period of pulse to "tame" the circuit and keep batteries cool .
Never charge a hot battery ( 110F ) , they dry up , short life .
Velleman has o'scope ( HPS-40 for $250 ) .

BTW
Clever battery chargers use a 2 step current limit , but more clever
is to make the heavy current , resistor controlled .
BTW Li-Ion need a charge rate of less than "c" til 3.6 to 3.65
VDC
at 25 Deg C . ( I.E. Sony 920 Notebook has 2.2 aH cells in parallel
so 4.4 times 3 sets in series
+12v in | |
| |
Ground | |
-means less than about 4 amps
til 3.6 vdc ...Thus the pow supply will show 4.9 amps to pow notebook
and charge both ( batts/Notebook) same time .

These Li-Ions are worth your while even if you are poor .
They will Kill Nicad/Nimh for they have
1) more energy per cubic inch ...
2) same VERY hi discharge rates .
3) but retain energy beyond a week .
dont fear paralleling , Li-Ions have much less cross talk ( discharge
of lower volt cell by the higher volt cell ) than anything ....


Off Topic Your Z-6 Minolta DigiCam will NOT like alkalines
You must use NimH for the hi power needed . And it dont like
heat , remove batteries to allow heat to escape for 15 minutes
and you can shoot again ... I guess refurbished can mean a
tax dodge , the Camera IS new ! The price drop is combo
of Loss Leader and a pass thru of tax .

__________________________________________________ ___________________________________


Dan_Musicant wrote:
I have a Panasonic 12v (NiCads) cordless drill/driver with 2 batteries
and it seems to me that the batteries aren't holding a charge very well.
They are around 3-4 years old, lightly used. They seem to charge too
quickly. If I leave them in the charger after the charger shows them as
fully charged and let them trickle charge, will that top them up? I
haven't been doing that.

Is this a loss of capacity of the batteries? Is there some way I can
restore the capacity of the batteries? Any experience with these? Thanks
for any ideas, info, suggestions, etc.

Dan