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Correct battery clibration after replacement

I bought a replacement battery from ifixit and installed it, then I followed the instructions:

"Calibrate your battery before using it: allow it to drain overnight, then charge it to 100% and drain it again until your MacBook Pro shuts down automatically. Charge it again and use it normally."

When I turned on my macbook after the replacement it showed a charge of 59%, then I used the the macbook until it turned off automatically, but the problem was it didn't go to hibernation on about 5% as usually, but it suddenly turned off on about 18% and all work in progress was lost. I tried everything including SMC and PRAM reset but the macbook stopped going into hibernation mode. I explained all of this in detail (including coconut battery screenshots) to the customer service and they send me a new battery saying the one I received was damaged.

Now I installed the 2nd new battery and turned the macbook for the first time on and it showed ca. 57% of charge and I continued discharging the battery by using the macbook and then I thought maybe I'm following the instructions wrongly.

The calibration instructions aren't entirely clear to me. For example the first part says "allow it to drain overnight". Does that mean I'm not supposed to turn on the macbook for the first time at all and the battery is going to discharge by itself to 0%? I don't believe the battery can drain to 0% after one night sitting in a turned off macbook, right? The second part of the instructions "then charge it to 100% and drain it again until your MacBook Pro shuts down automatically. Charge it again and use it normally" is pretty clear to me since it indicates you are supposed to use the macbook until it shuts down automatically.

So now I have a turned off macbook on ca. 40% of charge (initial delivered battery charge, 0 cycles) and I have no idea what to do since I'm afraid I could run into the same problems as first time. Could someone provide a clear step by step guide what to do after replacing the battery. Is it necessary to reset SMC again. If yes in which step? Thanks.

TL;DR: How to correctly calibrate the battery after replacement, step by step guide. What does "allow it to drain overnight" mean? To drain it by using the macbook or to let it drain in a turned off device (which would take way longer then only 1 night)? Is it necessary to reset SMC?.If yes in what step?

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So the solution for me was setting the hibernation mode to 25 instead of 3 by executing following command:

`sudo pmset -b hibernatemode 25`

Now the macbook goes into hibernation every time it reaches 5% and my work gets saved.

This hibernation mode is "deep" and it saves al the RAM content as an image to the disk.

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I have the same issue as you have! I just installed a new battery received from IFIXIT as a replacement for the previous new one I got because of this problem. And just like yours, it's also just shutting off (it seems that way) without any warning at around 20 %. It did this with the original battery and the 2 new ones I've just tried. Can you explain why this option works for you? I'm gonna try it now, but I wonder why having it at 3 (mine was also at 3) would cause the Macbook Pro to do this at 20 - 40 % battery left.

I understand that putting it to 25 will store RAM to disk instead of 3 storing to disk while also keeping it in RAM. But what's the difference here? They both write RAM to disk so in case of complete power loss your computer would still be able to get out of sleep by pulling your previous session from the disk. But what I want to know is does this solve the issue of getting shut off at 20 % so I can use it like before to 5% before it goes to sleep? And do you have any idea why this is?


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Here is an easy way to discharge.

a) First you absolutely need to go to Settings ---> Energy Saver --> Battery and check "Prevent computer from sleeping automatically".

b) Start a movie, either on iTunes or DVD or similar, and have it loop when the laptop is not plugged in. This will drain the battery (normally it will play the movie around 2 times depending the length of the movie, and the laptop will turn itself off either a hard shutdown from lack of power or sleep due to low power.

c) Then once this is done, charge fully and repeat 2-3 times. This should then properly calibrate the battery.

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Thanks for the advice. I did it just like you described but the macbook kept shutting down without going into hibernation (safe sleep) at 5%, but it drained the battery to 0% every time.


You asked to calibrate. If you had unchecked "prevent computer from sleeping automatically" after the calibration, it would have slept as normal. You show download coconut battery and make sure the status of your battery read correctly. http://www.coconut-flavour.com/coconutba...


You probably mean sliding the "Computer sleep" slider all the way to the right to the setting "Never" since there is no option as you describe it "prevent computer from sleeping automatically" (at least not in high sierra).

And yes I did turn both sliders all the way to the setting "never" and started a heavy task like a 4K movie, but the computer never went to sleep und just turned off. It doesn't make sense what you say since "prevent computer from sleeping automatically" has nothing to do with ensuring that the macbook will go to sleep as normal. The problem was exactly that it didn't do what you described it should do. And yes, the first thing I did when started troubleshooting was installing coconutBattery. It showed the correct battery level after 2 charging cycles.

Thanks for you feedback anyway.

I'm glad I solved this problem


You may be right. It's different depending on the OS X version. However, downloading coconut battery is still recommended health monitoring.


Cannot even log in after replacing the battery and rebooting it.


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Raif Tabucic will be eternally grateful.
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