Originally Posted by
nckmat
That's an old trick of lesser quality manufacturers so that if something goes wrong with your batteries they can say "ah you must have left them fully charged for more than two hours". Absolute rubbish, if this was the case then you wouldn't be able to leave a laptop or mobile phone turned off for more than two hours either.
A balance charged battery of decent quality can be left charged for days without any noticeable problem, it's not great for their lifespan, it may shorten it a few dozen cycles but when you can buy a 65C 6600mAh battery for under $50 who cares.
Laptop mobiles and other lower power devices do not charge the batteries to 100% state of charge to avoid potential problems whilst in storage and increase the cycle life of the battery. Depending on the application they are typically charged to 90%.
Charging a lipo to 100% the night before is not recommended as it can cause problems.
Best battery performance on track is obtained by charging lipos just before they are to be used. I charge mine so they finish charging just before my next race.