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Gah... calibrating the battery sucks.
- Thread starter SR71
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Calibration has nothing to do with "good" or "bad" batteries. The purpose is to make the battery readings more accurate. As Apple recommends:
To calibrate, you must first fully charge the battery, and since Apple has no way of knowing when a user will open the box and turn on the computer for the first time, they ship from the factory without a full charge, which is the proper way to store a battery.
Also, do I really need to leave the MBA unplugged for 5 hours. Like is it absolutely necessary? If I don't do it, will my MBA not be calibrated? Thanks for the answers, by the way.
If you're not going to do it properly, don't do it at all.
I just have a HD video looping in the background, and then if its close to drained, but I'm not ready to do it I just charge it periodically so it stays around 10% until I'm ready.
Not trying to steal thread here. I tried calibrating my battery today, and I got the warning that the mac is running on reserve battery and the percent is actually 0%. At that point, I tried to move the mouse to close the message and realized nothing is working, next thing I know the screen is off. My dumb ass thought the computer froze and died on me so I immediately pluggin the charger. Funny thing is the screen came back on and everything works again. Should I recalibrate again since I should've let it sleep for 5 hours and I didn't? Thanks in advance for the help
Yes. You need to start the process from the beginning. This time, when it shows you that message, leave it alone. You don't need to close the message, as it will go away on its own. Just let your battery drain and after your Mac powers off, leave it unplugged for 5+ hours before recharging it.
When you say leave it unplugged, do you mean unplugged and don't use it or unplugged and use it until it discharges again?
As the battery will not have much charge left at this point, you can't use it anymore, as it goes to sleep. It just takes another 4 to 5 hours to completely discharge the battery, as the battery still has approx. 3% of charge left, thus it needs approx. 5 hours to fully deplete.
Btw, as the battery is already discharged at this point, one can't discharge again without charging again.
You have read this already?
Actually, it's the exact opposite. Apple installs really good batteries from the start, almost always much better than the initial worse case estimate held by the battery controller before further calibration. That's why the battery gauge often doubles the amount of battery time remaining after a couple full discharge/charge cycles.
I agree with a previous post. The OP implies that calibrating is necessary for optimizing battery life. But it is not. Some times however, it is necessary for matching remaining battery time indicator (% counter) with the actual remaining battery time.
My MBA when fully charged and plugged in showed only 99% for example, but after a calibration it correctly showed 100%. But that doesn't mean i got 1% longer battery life.
My MBA when fully charged and plugged in showed only 99% for example, but after a calibration it correctly showed 100%. But that doesn't mean i got 1% longer battery life.
If you just use your laptop off the plug everyday you don't need to calibrate anything. i noticed every time i tried to calibrate the battery in the past the capacity goes down. maybe because the batteries arent meant to be completely drained and you could be prematurely wearing out your battery by draining it down to empty. do as you please but i would just not worry about calibrating anything and just enjoy using the laptop.