O
Oxide Blu
Guest
When the MacBook Pro is sitting on my desktop I have it plugged in to AC power but have the battery removed. This prevents the battery from going bad. The guys at the Apple Genius Bar recommend this in fact.
With the new models that have a non removable battery you can't do this. Bad for battery longevity.
I think that is one of those techno-wives tales held over from the NiCad battery days. Today mobile computers are using Li Ion batts, not the same problem with "training" like a NiCad.
Your battery will last longer if you leave it plugged in on a float charge. Your computer should be good for that. Batteries are a chemical process, always in a state of decay, no way to stop it. The best we can do is provide a stable environment to prolong the rate of decay. That is what a float charge does, a very low current at high voltage to keep the battery 'topped off' so that it isn't going up and down, e.g. "cycling".
A battery "cycle" is anytime you discharge a battery below 90% of its capacity, e.g. 10% discharge on your computer's batt meter. A battery can only be "cycled" (discharged/recharged) so many times (300 - 500 depending on depth of discharge), then it craps on your shoe. Leaving a battery in your computer keeps it from cycling, helps it to last longer. Without a float charge a Li Ion batt will self discharge at something like 5%/month. So in as little as 2-months, you lost 1 battery cycle by not leaving the batt in your computer.
The only way there is an advantage to removing your batt when your computer is on AC is if iApple does not have a modern battery charging scheme integrated into their laptops. I just don't see that.
Put your batt back into your computer when it is on AC. :thumbup:
ETA: there is a phenomonon with Li Ion batteries -- if totally 100% discharged a cell can reverse polarity. A battery is actually made up of several cells, in series, inside of the battery case. One of those cells can reverse polarity; e.g. the anode becomes the cathode, and vis a versa. Some folks have been able to recover from that situation, some cannot, battery must be trashed. Do not totally discharge a Li Ion battery.