Currently Being ModeratedApr 14, 2012 2:35 PM (in response to tengafro)
Calibration isn't necessary in modern Macs with built in batteries. That process didn't calibrate the battery, it calibrated the circuits that monitor the battery.
From the following article:
Portables with built-in batteries
Current Apple portable computer batteries are pre-calibrated and do not require the calibration procedure outlined in this article. These computers use batteries that should be replaced only by an Apple Authorized Service Provider.
Currently Being ModeratedApr 14, 2012 2:38 PM (in response to tengafro)
I believe the article says "at least 5 hours." So if you run down the battery during the day and leave it off, unplugged at night, that's fine.
Currently Being ModeratedApr 14, 2012 2:43 PM (in response to captfred)
are u sure that i dont have to calibrate it? because sometimes when i charge it to 100% and turn it off (also unplugg) when i turn it on another day it shows it is only charged to 98% but i dont know why since i turned it off.
Currently Being ModeratedApr 14, 2012 2:55 PM (in response to tengafro)
Some amount of battery discharge can be expected, even when it's turned off.
Currently Being ModeratedApr 14, 2012 2:58 PM (in response to captfred)
but it wasn't like this a month before
Currently Being ModeratedApr 14, 2012 2:59 PM (in response to tengafro)
He's saying the new macs don't require this to prevent the battery from forming a "memory." They also come pre optimized, so I guess you can get away with not doing this procedure. But if the battery levels/usage doesn't seem accurate, doing the calibration might cause the operating system to correctly show battery usage. In other words, the battery doesn't require calibration, but the software may, so there may be benefit in doing it.
Also keep in mind that these batteries are "smart." If you charge it to 100%, then use the battery for a minute, then use the wall outlet again, it won't start charging the battery until it falls below 95%, this is to prevent overcharging and damage to the battery--nothing to worry about. Also, during heavy usage (gaming) the battery might drop slightly and stop charging even when plugged in.