discharging nicad batteries???

[gothika]

I have some 9.6v nicad batteries for a cordless drill.
What is the best way to completely discharge these before
recharging?(I use a 12v tail light bulb for some 12v nicads but don't
think that would work in this case.)
I've seen a home brew box used to rapidly discharge badly formed
nicads thereby restoring them to some usable state.
Anyone know what it'd take to build one of these, or where I might
purchase one?
Thanks in advance for any assist.

 

[CJT]

I have some 9.6v nicad batteries for a cordless drill.
What is the best way to completely discharge these before
recharging?(I use a 12v tail light bulb for some 12v nicads but don't
think that would work in this case.)

I think it would.

 

[Sam Goldwasser]

I think it would.

If you completely discharge the entire pack, it will probably be damaged and
unusable since some cells will have been reverse charged in the process.

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[Jerry G.]

Use the 12 volt lamps. They will be of adequate load. You do not want
to overload the batteries as well. Never discharge NiCads fully. They
can be put down to about 40% below nominal, to have a proper discharge.
If you fully discharge them, they can also be damaged.

I use my drill to do the job. I turn the drill on in the lock position,
and leave it sit until it just about stops. Then I charge the battery
pack.

NiCad batteries will last about 2 to 3 years average, if used moderate
to light. They will last even less with a lot of heavy use. It is a
combination of age and charge cycles that wear them out. As they age,
they also degrade in their chemical makeup. There is no way out.

--

Greetings,

Jerry Greenberg GLG Technologies GLG
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I have some 9.6v nicad batteries for a cordless drill.
What is the best way to completely discharge these before
recharging?(I use a 12v tail light bulb for some 12v nicads but don't
think that would work in this case.)
I've seen a home brew box used to rapidly discharge badly formed
nicads thereby restoring them to some usable state.
Anyone know what it'd take to build one of these, or where I might
purchase one?
Thanks in advance for any assist.