Is this possible: Using 18650s from a tool battery individually?

[axstv]

I have a cordless Ryobi "12V" lithium drill. I believe the battery has three 18650s in it. Can I dismantle it and use the cells individually for different applications, then when the time comes gather the three cells back together for charging with the Ryobi charger(Which I like because it charges in 30 min)? I guess the cells would be unbalanced from their separate uses and would that be a problem? What other issues?

 

[adamlau]

Dismantle it and use the cells as in like this:
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I suppose you could solder, tack, or spot weld the cells back to the contact strips, but it would probably be easier to charge loose cells in the Pila IBC chargers you see above.

 

[scott.cr]

Hey Lau, what brand of cells were in that Ryobi battery pack? (Or if no brand is apparent, what are the markings on the cells?)

 

[mdocod]

Most Ryobi lithium packs are using the 18650 size Lithium Manganese Oxide cells made my Molicel. The 18V pack actually has 10 cells, the 12V pack I would guess has closer to 6 cells... For charging your best bet for fast charging would be a good bench power supply with adjustable voltage and current output limits, then build a cradle to mount the cells into in parallel for charging. In parallel the cells will balance out just fine. Charge ~3 amps per cell to get ~30 minute charging. Try not to put cells in parallel that are way out of balance to begin with, (check voltage beforehand, bring a really low cell up individually to be closer to the higher cell before putting them on the charger together, I'm going to take a stab/guess that as long as they are within ~0.25V they can be safely slapped on the cradle without a problem.)

If you are willing to deal with longer charging times, but just want convenience for cheap, any Li-Ion charger with termination around 4.20V will work on these type of cells.