Question about calibrating

if u connect ac adapter when your battery is at 97% 98 99 it will not reach the 100%,cause mac say it fully charged; you have to use till 90 % then charge again and you reach the 100


however retry calibration
follow this : remember that you just have to wait 5 hours minimum after reconnect the ac adaper, so don't mind if after five hours the light of stop still lighting..

To calibrate the battery:
Plug in the MagSafe power adapter and fully charge the MacBook or MacBook Pro battery until the light on the MagSafe connector changes to green and the Battery icon in the menu bar indicates that the battery is fully charged.
Allow the battery to rest in the fully charged state for two hours or longer. You may use your computer during this time as long as the power adapter is plugged in.
Disconnect the power adapter with the computer on and start using it with battery power. When the battery's charge gets low, you’ll see the low battery warning dialog on the screen.
Continue to keep your computer turned on until it goes to sleep. Save your work and close all applications when the battery's charge gets low and before the computer goes to sleep.
Turn off the computer or allow it to sleep for five hours or longer.
Reconnect the power adapter and leave it connected until the battery is fully charged. You may use your computer during this time.

ciao ciao
Alberto

All calibration instructions I've ever seen on the Apple website for Lithium batteries state that you just need to let it go to sleep.

That was true for Apple's laptops previously, but for the MacBook Pro and the most recent PowerBook models, the calibration instructions specify that the laptop must be left unplugged for at least five hours after the battery is drained and forced into sleep.

See Apple's current battery calibration article. (Scroll down towards the bottom for the instructions for the MacBook Pro, MacBook, and some recent PowerBook models.)

The reason this needs to be done, as stated in that article:

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.

Previous Apple laptops didn't require this step because they didn't maintain that reserve battery power.

iamapple, it sounds as if you haven't actually drained the battery before the computer was forced into sleep.

I'm not clear on whether you followed those instructions exactly.

Did you use the computer unplugged until it gave the warning it was using reserve battery power, then continue to use it until it was forced into sleep? After that, the procedure is to keep it unplugged for another five hours. (Obviously that last step is best done overnight, rather than being without your computer for all that time. ;-))

quoting from the MBP user guide (directly copied from downloaded guide by Apple):


To calibrate your battery:
1 Plug in the power adapter and fully charge your MacBook Pro battery until the light on
the power adapter plug changes to green and the Battery icon in the menu bar
indicates that the battery is fully charged.
2 Allow the battery to rest in the fully charged state for two hours or longer. You may use
your computer during this time as long as the adapter is plugged in.
3 Disconnect the power adapter with the MacBook Pro on and start running it from the
battery. You may use your computer during this time.
When your battery gets low, you’ll see the low battery warning dialog on the screen.
4 Continue to keep your computer turned on until it goes to sleep. Save your work and
close all applications when the battery gets low and before the system goes to sleep.
5 Turn off the computer or allow it to sleep for five hours or longer.
6 Connect the power adapter and leave it connected until the battery is fully charged
again.

unquote

Complete each step before continuing to next. If you attach to ac power before the five hours has elapsed, then you have defeated the purpose.

It is not unusual for a calibrated battery to still have a pulsing charge after the five hours. I calibrate about every month and generally still have pulsing led when the 5 has elapsed.

Message was edited by: Rhyd

You must let it go into emergency sleep and then leave it without power for at least 5 hours (ideally 7) before you plug it in and charge it fully. No wait = no calibration !

That is a tip, not needed, see below:

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

That's not a tip nor is it optional according to Apple. That is, as you note, step 5 for the calibration procedure.

And in Step 6, you plug the computer back in. Not before.

This is what Apple says to do to recalibrate the battery. Whether it's best practice with Lithium batteries or not, I couldn't tell you. I know what you're saying about draining Lithium batteries - but my understanding, based on Apple's instructions, is that these latest batteries are different or differently-managed and therefore require this step to calibrate properly. Beyond that - I'd suggest asking someone at Apple why the new instructions are necessary.

I ran down the battery until it gave me a warning and went down to 0% then went to sleep. Am I doing this wrong or what? The charge is now 99% and the health is 92%. Is this okay?

It's probably fine. Don't stress about this too much. 🙂

On the one hand, the battery is supposed to be drained to the point where the computer is forced into sleep and then left to sit (unplugged) for a period of time afterwards (as I understand it). So if all of that didn't happen, you technically didn't complete the calibration procedure.

On the other hand, battery calibration is only intended to make sure the charge your MBP reports is accurate. If it seems accurate, I wouldn't worry about it until that changes.

When in emergency sleep the setting isn't relevant ...

When re-charging the MacBook Pro it's best not to let it sleep again until the battery shows 95% plus re-charged.

All calibration instructions I've ever seen on the Apple website for Lithium batteries state that you just need to let it go to sleep. Deep sleep is not required for battery calibration, otherwise earlier Apple notebooks that did not support deep sleep would never be able to calibrate their batteries.

I realized after I posted that this was your interpretation.

This is something that has been debated at length before. Step 5 is worded badly in that article, regardless of what it actually means. 😉

The general consensus, at least amongst Level 4 members in the Lounge, has been that Step 5 means that you should turn off the computer for five hours or let it sleep for five hours, and then continue to Step 6.* But it is definitely ambiguous. I've asked for clarification on this from the Hosts before, and I'm asking them again now, because we really need a definitive answer and an edit to that article one way or the other.

*(The reason this has been the consensus: Shutting down and then moving on to Step 6 would have no influence over the reserve charge that Apple mentions in their footnote. Only by either letting the computer sleep for five hours or leaving it shut down for five hours would the result be what Apple says is intended.)

The directions were more clearly written in the user guide for my powerbook.

It said to let it sleep for at least five hours after it automatically went to sleep on low battery.

I guess that someone wanted to shut down instead of sleep so that Apple rewrote in order that sleep or shut down were both viable choices for the five hours.

(Of course, since I had the original directions, I could easily read the number five order of [shut down or sleep] as a set followed by the verb and length of rest required for correct calibration.)

That is not good at all. Your battery should stay above 80% for a while, not two days. For example, my last Apple notebook, a 1.42Ghz iBook G4, battery never went bellow 90% in over a year of use, even after several re-calibrations.

Here's another idea. Don't bother with all this calibration mumbo jumbo and enjoy it.

That's probably reasonable if your MBP is reporting an obviously accurate battery charge. But if and when it starts going into deep sleep while still showing a percentage charge remaining and without giving you any warning that it's running on reserve battery charge, one does need to calibrate the battery. In that situation I'd hardly call it mumbo jumbo. 😉

In my experience that will happen after a few months without calibrating the battery, depending on one's patterns of using the MBP on battery power vs. plugged in.

If you know anything about Lithium batteries then you know that dipping into that reserve is not a good idea and it really hurts the battery rather than helping the calibration. That is a tip, not needed, see below:

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

You quoted a section of the article that referred to a Tip in your earlier post, that is what I was referring too, not step five.

My point about step five is that it says you can turn it off and then recharge or wait five more hours, not that you have to wait five more hours, its optional from my understanding of the instructions and I think I know english well enough since it is the only language I know.