Happy Christmas all!
I've been given a Bosch GSB120-Li drill/driver as a pressie for Christmas with two 12v 1.5Ah Li-ion batteries. This is the first Li-ion battery tool I have had and have previously relied on my 50+ year old corded B&D for my occasional DIY use, but it's now on it's last legs.
I'm unsure how best to look after the batteries. How long can I leave a fully charged battery in the drill without use before the battery charge deteriorates? Can I leave a partially charged battery in the drill for long periods? How long will the alternative battery remain fully charged? Should I leave a battery in the charger, switched on, while not being used? Should I periodically recharge both batteries? Do I have to fully discharge the batteries before re-charge? The instruction manual is no use in answering these and many other questions I have so any advice would be appreciated.

Cheers
Pete