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

The traditional way to erase battery memory is to deep-cycle the
battery. For a drill/driver, I would use it until the thing hardly
turns at all, then find a way of clamping the trigger down so as to
completely drain the battery. You want to get it as close to 0VDC as
possible. After that, fully charge the unit and see if the memory has
been erased.







In article , 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

That is very good advice, providing your goal is to kill the cells entirely.
You should not completely discharge NiCd batteries. Read
http://www.repairfaq.org/ELE/F_NiCd_...ICDBATTERY_005 for a
reasonably technical discussion of this and other properties of NiCds.

todd

"Andrew Williams" wrote in message
news:050820061757313000%andrewSPAMALOT@williamsmus ic.com...
The traditional way to erase battery memory is to deep-cycle the
battery. For a drill/driver, I would use it until the thing hardly
turns at all, then find a way of clamping the trigger down so as to
completely drain the battery. You want to get it as close to 0VDC as
possible. After that, fully charge the unit and see if the memory has
been erased.







In article , 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

On Sat, 05 Aug 2006 21:47:47 GMT, 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

Four years is past the maximum life of a nicad even you you have
only used them lightly.

If you love that drill a lot, you can order new batteries and solder
them in.

In article ,
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

Some chargers have a diagnostic or "tune-up" mode that may help if you
leave the batteries in for an extended time, so it's worth trying.
Unfortunately, at 3 to 4 years it would be common to see some
degradation in the performance of a nicad, regardless of how much use
they have had.




--

Larry Wasserman Baltimore, Maryland

True.

"todd" wrote in message
. ..
That is very good advice, providing your goal is to kill the cells
entirely.

In article om,
Andrew Williams wrote:
The traditional way to erase battery memory is to deep-cycle the
battery. For a drill/driver, I would use it until the thing hardly
turns at all, then find a way of clamping the trigger down so as to
completely drain the battery. You want to get it as close to 0VDC as
possible. After that, fully charge the unit and see if the memory has
been erased.



This is indeed the traditional way and it is also NOT a good idea. The
"memory effect" is pretty much a myth for multicell nicads used in
cordless power tools. Letting the batteries fully discharge is also
potentially harmful to the battery. When all the cells are fully
discharged, it becomes possible for one or more of them to go into a
reversed polarity state. Once this happens that cell becomes
permanently useless. For a good quality cordless tool with a "smart"
charger (most any DeWalt, Makita, Milwaukee, etc.) the best place to keep
a battery is in a plugged-in charger. For cheaper cordless tools (like
Harbor Freight's) with a "dumb" charger, remove the battery after the
recommended charging time.
--

Larry Wasserman Baltimore, Maryland

wrote:

When all the cells are fully discharged, it becomes possible
for one or more of them to go into a reversed polarity state.

I'd say it's an inevitable consequence of the fact that
individual cells cannot be fully balanced for all charging
parameters when assembled into a battery of cells.

The only way of ensuring maximum life from such a battery (where
individual cells aren't accessible) is to do the occasional
"equalization" charge, overcharging at a trickle rate until the
weakest cell (the one which leaks the most charge) has had time
to come up to full charge.

John

Dan_Musicant wrote in
:

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.

some chargers are designed to be able to leave the pack in,some are not.
You need to check your manual.

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

It's been my experience that for longest life,NiCds are best used
often.(use it or lose it)
Once you start storing them for long periods,their life decreases.
NiCds also have a self-discharge rate;just sitting in storage,they
discharge on their own.



--
Jim Yanik
jyanik
at
kua.net

Andrew Williams wrote in
news:050820061757313000%andrewSPAMALOT@williamsmus ic.com:

The traditional way to erase battery memory is to deep-cycle the
battery. For a drill/driver, I would use it until the thing hardly
turns at all, then find a way of clamping the trigger down so as to
completely drain the battery. You want to get it as close to 0VDC as
possible. After that, fully charge the unit and see if the memory has
been erased.







In article , 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



then find a way of clamping the trigger down so as to
completely drain the battery.

Long/joined twistie ties, tie wrap, string are a few ways.

"Al Bundy" wrote in message
...
Long/joined twistie ties, tie wrap, string are a few ways.

To kill your batteries

On Sat, 05 Aug 2006 21:47:47 GMT, 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


I read the responses below that state you should not drain the battery
but when I googled
*NiCad Batteries Drain Completely*
there are articles that state you should drain them.
Here are a few of the articles....
http://www.nyu.edu/its/pubs/connect/...rdslaptop.html
http://www.ehow.com/how_3037_battery-life-laptop.html

Frankly, I have no idea which is correct (and I did see some articles
to the opposite) but if I'd suggest calling Panasonic tech service.

A lot of good info here, but I have some also to offer.

The key problem is "lightly used" - that means the NiCd cells will develop a
memory, unlike more modern ones. A memory of being charged, then
leak-discharged, then trickle charged, etc, etc. The only good way around
avoiding this, is using (as others have said) a discharge cycle (or use to
flat) before recharging, and not leaving them flat.

The age of the cells has NOTHING to do with the expected performance, as
long as you have cycled them properly. I have NiCd cells still working
strongly from the mid nineties.

wrote in message
...
In article ,
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

Some chargers have a diagnostic or "tune-up" mode that may help if you
leave the batteries in for an extended time, so it's worth trying.
Unfortunately, at 3 to 4 years it would be common to see some
degradation in the performance of a nicad, regardless of how much use
they have had.




--

Larry Wasserman Baltimore, Maryland

Joe Bemier wrote:

I read the responses below that state you should not drain the battery
but when I googled
*NiCad Batteries Drain Completely*
there are articles that state you should drain them.
Here are a few of the articles....
http://www.nyu.edu/its/pubs/connect/...rdslaptop.html
http://www.ehow.com/how_3037_battery-life-laptop.html

Frankly, I have no idea which is correct (and I did see some articles
to the opposite) but if I'd suggest calling Panasonic tech service.

Draining a NiCd or NiMH cell completely means to remove essentially all
the energy it contains. This requires discharging it to a cell voltage
of about 1.0 volt. Doing this, then recharging, is the way to reverse
"memory" (voltage depression) effects. If the battery has 6 cells or
fewer and they're reasonably well matched, you can usually safely
discharge the battery to 1.0 volt times the number of cells (e.g., 6.0
volts for a 6 cell battery) without risk of reverse charging one of the
cells. If the battery has more cells, this becomes increasingly risky
and the only safe way to do it is to discharge the cells in groups of
4-6. This of course requires getting into the battery pack.

The folks cautioning against trying to discharge down to 0 volts are
absolutely correct. It just about guarantees reverse charging one or
more cells, which will permanently damage those cells. Those cells will
then have even more reduced capacity, so they'll go into reverse charge
even earlier in the battery cycle the next time. There's never any need
to discharge a cell below 1.0 volt. A well designed tool or electronic
device intended for NiCd or NiMH power should quit operating and drawing
battery current when the pack voltage reaches 1.0 volt per cell.
Unfortunately, a lot aren't in this category.

Roy Lewallen

I find nicads in drills last about two years. You got your use out of
them.

--

Christopher A. Young
You can't shout down a troll.
You have to starve them.
..

"Dan_Musicant" wrote in message
...
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

Jim Yanik wrote:
Dan_Musicant wrote in
:

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.

some chargers are designed to be able to leave the pack in,some are not.
You need to check your manual.
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

It's been my experience that for longest life,NiCds are best used
often.(use it or lose it)
Once you start storing them for long periods,their life decreases.
NiCds also have a self-discharge rate;just sitting in storage,they
discharge on their own.



Probably right about the use or lose it.

If you don't use them much you need to keep
checking the voltage at least once every 1-2
months and make sure the voltage doesn't drop
below 12V. Full charge on a 12V NiCad is about
14V, but that degrades quickly to about 13V and I
check the voltage when charging and stop before it
reaches 14V. Overcharging is the number one cause
of batteries going bad.

"todd" wrote in message
. ..
That is very good advice, providing your goal is to kill the cells
entirely. You should not completely discharge NiCd batteries. Read
http://www.repairfaq.org/ELE/F_NiCd_...ICDBATTERY_005 for a
reasonably technical discussion of this and other properties of NiCds.

todd

I have two drills, a Makita and a Sears. The Makita is over 10 years old
with the original two Batteries, the Sears is about 6 years old with the
same two batteries. I always let the drill run down to where it stops
turning or pretty close to stopping before recharging. Who knows, but it
worked for me. I didn't do this at first, and after about 2 years one of
the Makita batteries stopped holding a charge. From something I read on the
internet (what the hell, it was worth a try) I took the 12 volts from my
car battery charger and quickly touched it on the baterry contacts a couple
times, sure enough the battery started working again, and it still works 8
years later! Regardless, I will make sure my next drill uses Nimh
batteries.

On Sun, 06 Aug 2006 04:39:49 GMT, "George E. Cawthon"
wrote:

Joe Bemier wrote:
On Sat, 05 Aug 2006 21:47:47 GMT, 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


I read the responses below that state you should not drain the battery
but when I googled
*NiCad Batteries Drain Completely*
there are articles that state you should drain them.
Here are a few of the articles....
http://www.nyu.edu/its/pubs/connect/...rdslaptop.html
http://www.ehow.com/how_3037_battery-life-laptop.html

Frankly, I have no idea which is correct (and I did see some articles
to the opposite) but if I'd suggest calling Panasonic tech service.

That's the problem with netnews and the Internet
in general. Lot's of incorrect stuff that gets
repeated over and over even by groups that should
know better.
Always check major manufacturers for the accurate
information when there is controversial information.


Yes, and that includes the opinions that ppl are posting here - who
knows which way to lean. Thats why I say calll Panasonic.

JimL wrote:

Four years is past the maximum life of a nicad even you you have
only used them lightly.

Maybe my 10-year-old nicads never read the book :-)

ToMh wrote:


"todd" wrote in message
. ..
That is very good advice, providing your goal is to kill the cells
entirely. You should not completely discharge NiCd batteries. Read
http://www.repairfaq.org/ELE/F_NiCd_...ICDBATTERY_005 for a
reasonably technical discussion of this and other properties of NiCds.

todd

I have two drills, a Makita and a Sears. The Makita is over 10 years old
with the original two Batteries, the Sears is about 6 years old with the
same two batteries. I always let the drill run down to where it stops
turning or pretty close to stopping before recharging. Who knows, but it
worked for me. I didn't do this at first, and after about 2 years one of
the Makita batteries stopped holding a charge. From something I read on
the
internet (what the hell, it was worth a try) I took the 12 volts from my
car battery charger and quickly touched it on the baterry contacts a
couple times, sure enough the battery started working again, and it still
works 8
years later! Regardless, I will make sure my next drill uses Nimh
batteries.

Next time you're in Home Despot or the like check out the 36v lithium-ion
deWalts.

--
--John
to email, dial "usenet" and validate
(was jclarke at eye bee em dot net)

"Stormin Mormon" wrote in message
...
I find nicads in drills last about two years. You got your use out of
them.


Usually nicads are rated in how many charge cycles they can take. Around
300 to 600 cycles. I think that a partical charge is also a partical cycle
but not sure. Some rechargables are just rated in number of years even if
they are not used very often.

Ralph Mowery wrote:
"Stormin Mormon" wrote in message
...
I find nicads in drills last about two years. You got your use out of
them.


Usually nicads are rated in how many charge cycles they can take. Around
300 to 600 cycles. I think that a partical charge is also a partical cycle
but not sure. Some rechargables are just rated in number of years even if
they are not used very often.


True, LiOn Cells will only have a useful life of about two years, after
that they should be replaced, the same is true for LiPo batteries.

John McFerren wrote:

Ralph Mowery wrote:
"Stormin Mormon" wrote in message
...
I find nicads in drills last about two years. You got your use out of
them.


Usually nicads are rated in how many charge cycles they can take. Around
300 to 600 cycles. I think that a partical charge is also a partical
cycle
but not sure. Some rechargables are just rated in number of years even
if they are not used very often.


True, LiOn Cells will only have a useful life of about two years, after
that they should be replaced, the same is true for LiPo batteries.

I keep hearing this. My real world experience is otherwise.

--
--John
to email, dial "usenet" and validate
(was jclarke at eye bee em dot net)

On Sun, 06 Aug 2006 05:25:44 GMT, "ToMh" wrote:

:Regardless, I will make sure my next drill uses Nimh
:batteries.

I got the NiCads because the drill came cheaper that way. It's true that
NiMH will have greater capacity. They say that the modern NiCads don't
have the memory effect, but I don't know if that's categorically true.
However, something to consider is the fact that NiMH will self-discharge
at a significantly higher rate than NiCads. For me, that's a very
important factor because most of the energy drain on my cordless drill
batteries is from sitting around, not from use. I think I'll stick with
NiCads for that reason.

Dan_Musicant wrote:

most of the energy drain on my cordless drill
batteries is from sitting around, not from use. I think I'll stick with
NiCads for that reason.

If you are letting the thing sit around a lot, get lithium batteries. The
self-discharge of NiMH is overstated by many - they do discharge faster than
NiCd, but not outrageously so. Li Ion, OTOH, will stay charged for long
periods. However, the life of a Li battery is more closely tied to state of
charge than to number of charge/discharge cycles. If it sits around fully
charged a lot, it will not last as long as if it's allowed to sit around
partially charged.

Mike

Dan_Musicant wrote in
:

On Sun, 06 Aug 2006 05:25:44 GMT, "ToMh" wrote:

:Regardless, I will make sure my next drill uses Nimh
:batteries.

I got the NiCads because the drill came cheaper that way. It's true that
NiMH will have greater capacity. They say that the modern NiCads don't
have the memory effect, but I don't know if that's categorically true.
However, something to consider is the fact that NiMH will self-discharge
at a significantly higher rate than NiCads. For me, that's a very
important factor because most of the energy drain on my cordless drill
batteries is from sitting around, not from use. I think I'll stick with
NiCads for that reason.


Do NiMH short out or fail if self-discharged,like NiCds?
If not,then they can be stored,then simply charged up before use,-without
needing to buy new packs.

--
Jim Yanik
jyanik
at
kua.net

On 6 Aug 2006 05:58:34 -0400, wrote:

:JimL wrote:
:
: Four years is past the maximum life of a nicad even you you have
:only used them lightly.
:
:Maybe my 10-year-old nicads never read the book :-)

Indeed, I have NiCads that must be 8+ years old, are in many seasons
very very seldom used and they seem to be reasonably adequate. I suspect
I can revive my drill NiCads. I'm not shopping just yet.

Dan

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 .

-----------------------------------------------------------------------
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

Months ? Nicads ? Wet Cell , in a plane ... OK .
Dry types? from da store , for your drill ? naaaaaah .
50% in a 20 days !!

Li-Ion is high rate power , loss can be 1% /month .
priced out of reach , ..... I tossed all my Nimh !
Just too good to be intimadated by price !
But they die if too much amps charge above the 3.65 vdc level .

All batteries will float if the amps are very low .

( BTW Harbor Fright tiny driver $20 , w/ Li-Ion has no greater than
a 1 aH single cell ) .


George E. Cawthon wrote:
Jim Yanik wrote:
Dan_Musicant wrote in
:

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.

some chargers are designed to be able to leave the pack in,some are not.
You need to check your manual.
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

It's been my experience that for longest life,NiCds are best used
often.(use it or lose it)
Once you start storing them for long periods,their life decreases.
NiCds also have a self-discharge rate;just sitting in storage,they
discharge on their own.



Probably right about the use or lose it.

If you don't use them much you need to keep
checking the voltage at least once every 1-2
months and make sure the voltage doesn't drop
below 12V. Full charge on a 12V NiCad is about
14V, but that degrades quickly to about 13V and I
check the voltage when charging and stop before it
reaches 14V. Overcharging is the number one cause
of batteries going bad.

werty wrote:

NimH and Nicad lose 10% in 1 day...

Would you have any evidence for this article of faith? :-)

Nick

In article , Jim Yanik wrote:
Keith Williams wrote in
ET:

In article .com,
says...
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 .

Nonsense. NiCDs and NiMH batteries love to be discharged.

Agreed.

That's
the only way to store them for long periods.

That's wrong.
They should be stored CHARGED.
Do you have any cites for your claim?

Don't "reverse
charge" cell(s) in a multi-cell battery by discharging it below
about 1V/cell though. They can be left to self discharge without
damage. A single cell battery can be discharged to zero.

OTOH, lead-acid batteries must never be fully discharged and must
be stored with a float charge. Lead-acid batteries are thus better
for things like flashlights, UPSs, safety lighting, and such.

----------------
2) NimH and Nicad lose 10% in 1 day , Li-Ion lose 1% .

Not any more. NiCds may be 20% per month, usually less.

NiCd Figures I've seen are ~5% self-discharge/day.
Storage temperature greatly affects this.

I have seen datasheets for NiMH cells indicating that the self discharge
rate decreases as self discharge progresses. A cell could self-discharge
5% in a day but less than 20% in a week. I would suspect NiCd can do
something similar.

- Don Klipstein )

"werty" wrote in
oups.com:

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 .

-----------------------------------------------------------------------
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



It is less painful to buy new batteries than read that post :-)

In article ,
says...
Keith Williams wrote in
T:

In article .com,
says...
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 .

Nonsense. NiCDs and NiMH batteries love to be discharged.

Agreed.

That's
the only way to store them for long periods.

That's wrong.
They should be stored CHARGED.
Do you have any cites for your claim?

Yes, Gates' secondary battery manual. The chemical reaction stops
with zero terminal voltage. They store quite nicely that way. In
any case, they *will* self discharge and the worse thing possible
for a NiCd or NiMH is to float charge it. THis is exactly the
opposite as is the situation for Lead-acid cells.

Don't "reverse
charge" cell(s) in a multi-cell battery by discharging it below
about 1V/cell though. They can be left to self discharge without
damage. A single cell battery can be discharged to zero.

OTOH, lead-acid batteries must never be fully discharged and must
be stored with a float charge. Lead-acid batteries are thus better
for things like flashlights, UPSs, safety lighting, and such.

----------------
2) NimH and Nicad lose 10% in 1 day , Li-Ion lose 1% .

Not any more. NiCds may be 20% per month, usually less.

NiCd Figures I've seen are ~5% self-discharge/day.
Storage temperature greatly affects this.

Nonsense. They do *not* self discharge totally in a month.
....more like 20% a month. Classically NiMH self-discharges at
about twice the rate of NiCD, but AIUI they've gotten much closer.

--
Keith

In article , krw wrote:
In article ,
says...
Keith Williams wrote in
T:

In article .com,
says...
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 .

Nonsense. NiCDs and NiMH batteries love to be discharged.

Agreed.

That's
the only way to store them for long periods.

That's wrong.
They should be stored CHARGED.
Do you have any cites for your claim?

With my Johnson walkie talkies with the42 year old NiCads, i charge some every year or two.
I have never found them totally dead.

greg

Yes, Gates' secondary battery manual. The chemical reaction stops
with zero terminal voltage. They store quite nicely that way. In
any case, they *will* self discharge and the worse thing possible
for a NiCd or NiMH is to float charge it. THis is exactly the
opposite as is the situation for Lead-acid cells.

Don't "reverse
charge" cell(s) in a multi-cell battery by discharging it below
about 1V/cell though. They can be left to self discharge without
damage. A single cell battery can be discharged to zero.

OTOH, lead-acid batteries must never be fully discharged and must
be stored with a float charge. Lead-acid batteries are thus better
for things like flashlights, UPSs, safety lighting, and such.

----------------
2) NimH and Nicad lose 10% in 1 day , Li-Ion lose 1% .

Not any more. NiCds may be 20% per month, usually less.

NiCd Figures I've seen are ~5% self-discharge/day.
Storage temperature greatly affects this.

Nonsense. They do *not* self discharge totally in a month.
....more like 20% a month. Classically NiMH self-discharges at
about twice the rate of NiCD, but AIUI they've gotten much closer.