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View Full Version : Do you -need- to calibrate the battery?




Laes
Jan 3, 2011, 04:10 PM
Hey,

My Macbook Air looks like it'll be getting delivered today and I had a quick question about battery calibration

I see that on here (http://support.apple.com/kb/ht1490) Apple recommend to do this on first use of getting the computer, but I wanted to know how much it would really matter if I didn't?

Pretty much the bit that will be annoying about it is step 5 where you are meant to leave it sleeping for 5 hours after fully draining the battery - I just want to use it like I normally would straight out of the box

Will it decrease the overall longterm performance of the battery if I don't calibrate on first use?



newdeal
Jan 3, 2011, 04:29 PM
No its just so your time remaining is more accurate. It is a good idea to fully drain it every once in awhile to keep it healthy but you don't need to do it the first time. Personally though I would just charge it up then use it and hope it dies right before bed so it can sleep overnight and then recharge the next morning

ECUpirate44
Jan 3, 2011, 04:32 PM
Apple suggests that you calibrate when you get it and then once a month after that to improve the accuracy of battery timers. It will not make your battery last longer. Its fine if you do not calibrate it every month.

GGJStudios will post the Apple notebook battery FAQ in a few minutes...

Hellhammer
Jan 3, 2011, 04:34 PM
You don't have to do it but the remaining battery time will be reported much more accurately. For me, it used to jump from 2 hours to 16 hours and so on but after calibrating, it's actually pretty accurate. I did it like few days after I got it. IMO the best way to do it is to drain the battery just before you go to bed (you can use heavy apps to drain it more quickly if you want to) and then leave it overnight and plug-in the charger before you go to work/school. Causes little to no trouble because you should be asleep for that 5-hour period.

KPOM
Jan 3, 2011, 04:35 PM
Apple suggests that you calibrate when you get it and then once a month after that to improve the accuracy of battery timers. It will not make your battery last longer. Its fine if you do not calibrate it every month.

GJStudios will post the Apple notebook battery FAQ in a few minutes...

It's actually quite difficult to follow the calibration steps now that the MacBook Airs go into "deep sleep." I downloaded Caffeine to force the system to stay awake long enough to drain the battery, but since I have gone through all of 11 cycles in the 1.5 months I've had my Rev D, I likely won't be calibrating it very often.

wordoflife
Jan 3, 2011, 04:36 PM
Hey,

My Macbook Air looks like it'll be getting delivered today and I had a quick question about battery calibration

I see that on here (http://support.apple.com/kb/ht1490) Apple recommend to do this on first use of getting the computer, but I wanted to know how much it would really matter if I didn't?

Pretty much the bit that will be annoying about it is step 5 where you are meant to leave it sleeping for 5 hours after fully draining the battery - I just want to use it like I normally would straight out of the box

Will it decrease the overall longterm performance of the battery if I don't calibrate on first use?

You don't need to but its recommended. I still haven't calibrated mine yet and this MBP is about 3-4 weeks old haha. :)

I'll probably get around to doing it eventually. If anything though, make sure you don't keep the computer plugged in 24/7. If that is what you plan to do, just make sure you use the battery every few days to keep the juices flowing through.

ECUpirate44
Jan 3, 2011, 04:37 PM
It's actually quite difficult to follow the calibration steps now that the MacBook Airs go into "deep sleep." I downloaded Caffeine to force the system to stay awake long enough to drain the battery, but since I have gone through all of 11 cycles in the 1.5 months I've had my Rev D, I likely won't be calibrating it very often.

What if you do as Hellhammer suggests and run CPU intensive apps until it dies?

Hellhammer
Jan 3, 2011, 04:41 PM
What if you do as Hellhammer suggests and run CPU intensive apps until it dies?

It will still likely enter the sleep mode but Apple says that is just fine.

5. Turn off the computer or allow it to sleep for five hours or more.

When the battery reaches "empty", the computer is forced into sleep mode. The battery actually keeps back a reserve beyond "empty", to maintain the computer in sleep for a period of time. Once the battery is truly exhausted, the computer is forced to shut down. At this point, with the safe sleep function introduced in the PowerBook G4 (15-inch Double-Layer SD) computers, the computer's memory contents have been saved to the hard drive. When power is restored, the computer returns itself to its pre-sleep state using the safe sleep image on the hard drive.

http://support.apple.com/kb/ht1490

Laes
Jan 3, 2011, 04:41 PM
Awesome thanks for all the replies :D

Should be awesome when it comes, no regrets about buying it even with Sandy Bridge being announced

leowyatt
Jan 3, 2011, 04:50 PM
I got my air on Christmas day, used it daily and have only just calibrated it today.

To drain the battery once charged I just put a 1080p copy of Avatar on loop. With 100% brightness on I got around 3:30 hours out of it before it went to off. Left it like that overnight and charged it up this morning.

To calibrate it I'd suggest getting yourself a copy of watts. I takes you through all the different steps :)

KPOM
Jan 3, 2011, 05:25 PM
I got my air on Christmas day, used it daily and have only just calibrated it today.

To drain the battery once charged I just put a 1080p copy of Avatar on loop. With 100% brightness on I got around 3:30 hours out of it before it went to off. Left it like that overnight and charged it up this morning.


That's effectively what I did, too. I found that CNet 720p oodcast content doesn't use hardware acceleration, so it really taxes the CPU and drains the battery quickly. I left Caffeine running to prevent it from going to sleep. I think it drained in about 3 hours.

Hellhammer
Jan 3, 2011, 05:39 PM
That's effectively what I did, too. I found that CNet 720p oodcast content doesn't use hardware acceleration, so it really taxes the CPU and drains the battery quickly. I left Caffeine running to prevent it from going to sleep. I think it drained in about 3 hours.

CPUTest (http://www.coolbook.se/CPUTest.html) is a good app for that as well. It maxes out the CPU and you can set it to run as long as you want. I've used it to test temps with my Macs but it should be suitable for this task too.

damnyooneek
Jan 4, 2011, 10:13 AM
every couple of days just unplug it and use it. no need to calibrate a new laptop.

farmermac
Jan 4, 2011, 11:35 AM
Handbrake works great at draining a CPU too

Might as well do something productive while draining your battery

GGJstudios
Jan 4, 2011, 12:59 PM
every couple of days just unplug it and use it. no need to calibrate a new laptop.
There is a need to calibrate a new laptop, if you want your battery readings to be accurate.

This should answer most, if not all, of your battery questions: Apple Notebook Battery FAQ (http://forums.macrumors.com/showpost.php?p=9875442&postcount=23)

aldo818
Jan 5, 2011, 03:33 AM
i calibrated my MBA and the time is pretty accurate the only thing which confuses me my Batterie health is always arround 96% the best i got was 97% the worst 94%. I only have like 30 cycles. Is there a prob with my batterie?
Is it due to the fact that i use my MBA all day long as primary computer ?

GGJstudios
Jan 5, 2011, 02:04 PM
i calibrated my MBA and the time is pretty accurate the only thing which confuses me my Batterie health is always arround 96% the best i got was 97% the worst 94%. I only have like 30 cycles. Is there a prob with my batterie?
Is it due to the fact that i use my MBA all day long as primary computer ?
Read the Battery FAQ I just posted. The section "CHECKING STATUS AND HEALTH" has your answer.