What is best way to store batteries

[Ron B]

I am a weekend warrior that just switched to Festool in the last year.  I have a PSBC420 jigsaw and noticed my Bluetooth battery is dead.  The battery was left in the saw and last used about 3-4 months ago.  I cannot get the battery to charge.  I did try to heat it up to 115 degrees but that did not work.  (Yes, I heated it to 115 F, not 115 C.).  I read that the TSC saws can drain batteries to the point of no return, and am wondering if that is what my 420 did.  I want my batteries to last as long as possible so plan to no longer store the batteries in the tool.  My question-to keep batteries as long as possible, how much charge should I leave in battery?  Also, how long is the warranty on the batteries?  Batteries are stored in climate controlled dry basement.  Any other tips on extending battery life would be helpful.

 

[squall_line]

Not an official Festool answer, but I work with clients who use iPads, so I know that Apple recommends the following for long-term storage of their iPads and iPods, which use Li-Ion batteries:

• Do not fully charge or fully discharge your device’s battery — charge it to around 50%. (If you store a device when its battery is fully discharged, the battery could fall into a deep discharge state, which renders it incapable of holding a charge. Conversely, if you store it fully charged for an extended period of time, the battery may lose some capacity, leading to shorter battery life.)
• Power down the device to avoid additional battery use.
• Place your device in a cool, moisture-free environment that’s less than 90° F (32° C).
• If you plan to store your device for longer than six months, charge it to 50% every six months.

Obviously you can't remove a battery from an iPad but Apple is pretty good at eliminating drain while powered down.  As you mentioned, removing the battery from the tool will eliminate the possibility of parasitic draw from the tool itself. 

I'm not sure how much parasitic drain is caused by the bluetooth or the charge indicator lights on the batteries.