Discharging NiCad Cordless Battery Pack

[newsomer]

Hello, first post here.

I know NiCad recharging has been discussed extensively here. I know this because I tried to research my answer by searching previous discussions and didn't find anything that would answer my question completely.

I have a three year old set of Craftsman 18 volt NiCad cordless drill and flashlight. What I would like to know is that if I use the battery in the drill until it is to weak to perform satisfactorily then swap it into the flash light and leave it burning until the light goes out will there be enough resistance in the light bulb to prevent the battery from discharging completely and ruining the battery pack?

To infinity and beyond!

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[ransley]

By the time the drill is slowed nicads are discharged, any further running or draining them risks reversing cells polarity. A nicad is fully charged at about 1.35v a cell and discharged at 1.2. What you propose will ruin your pack

[AZ Nomad]

1) nobody uses nicads any more. It is probably NIMH which work similarly but give longer life and require more carefull charging. Lithium Ion is now replacing NIMH. 2) When the the drill starts to run slower, discontinue use of the battery IMMEDIATELY! What kills rechargeable batteries is when the weakest cell is discharged and the rest of the battery is forcing current through it, in effect charging the weakest cell in reverse which will short it out.

Then charge it! Don't f*ck around by swapping it around. The only place to put the battery is back in the charger. If you put it in the flashlight and keep running it, you'll quickly ruin it.

I've also found that batteries left discharged will get ruined. I've used rechargeables for decades and the only time they've ever failed me is when I've stopped using a set for a long time. Recharge them periodically to prevent discharging.

[ransley]

ace to put

I've

I just bought Nicads yesterday, I didnt feel 3.5x the price for LiIon was worth it for occasional use. Also let the pack rest a day to cool before recharging, cells work by a chemical reaction , letting packs rest has gotten me 20 years on packs. Heat also kills cells, as in overcharging and rapid discharge,

[AZ Nomad]

There is always a "weakest cell". It isn't that he's running it past 1.2V. What he is doing is forcing current through a 0V cell, charging it in reverse.