1. Use your T3 for a lengthy period until battery at least half way down or more. don't worry about "excessive;" it'll switch off if you're in "danger," after giving a couple of warnings.
2. Charge it for 2-3 hours. I leave mine on the charger probably too long; it's on the charger most of the time I'm on the PC which can be considerable. It's not shown any "weakness" in the 8 months I've had it.
3. If you don't need beaming, TURN IT OFF. If you don't need Bluetooth, TURN IT OFF. Set the brightness to about "half of half" or 1/4 full brightness. If you're used to "all the way up, this may seem "dark," but you'll get used to it and believe me it's better than the 505 used to be!
These steps should give you DRAMATICALLY longer battery life and more rapid charges. Routinely, I'd say leave it OFF on the charger for an HOUR and you'll be fine.
I always wonder about voltage used vs getting a charge while unit is on in the cradle; it seems to deplete the battery to a certain point before "taking a charge" even though the little lightning bolt is displayed. Therefore it's not getting the full "oomph" of leaving it off for an hour.
That's been my pattern, and the battery has not weakened at all in 8 months of being on for an hour or more per day and charging for about the same or more each day, too.