quote:
Originally posted by Moh
Others believe that it doesn't really matter and does not in any way affect the battery since when the battery's fully recharged AC power will take over and won't affect the battery.
I would assume that is true on most laptops. The laptop is smart enough to know when the battery is full. Even a cheap regular battery loader is smart enough to cut power to the battery when the battery is full (or do a trickle load).
quote:
Originally posted by djdannyp
to get the longest battery life when you're using it on battery you should also let it run out completely before charging it back up again. This is true of ANY device with a rechargeable battery, not just laptops.
I think you're referring to the
memory effect, this is true for NiCd batteries, but AFAIK it doesn't apply to NiMH batteries which almost every laptop now uses. People always seem to contradict each other on these things though, so I would like a definitive answer too
.
Personally always ignore the "only charge when it is empty" and "don't leave it connected when it's full" advise. It certainly was true for NiCd batteries and dumb chargers, but it seems just old fashioned advise today. It's not like I will let my phone/battery run out on purpose to find myself with 0% power somewhere where there isn't an power outlet in reach. And it's not like I will wake up in the middle of the night to disconnect my phone from my charger because it is ready. Even if it were better for my batteries. I charge my phone every night whether it's needed or not. When you sync a phone over USB it will also start charging whether you want to or not. Laptops are plugged into a power outlet whenever one is in close reach.
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